^Aavaan-i^ 


THE    MONTHLY    BULLETIN 
CALIFORNIA  STATE  DEPARTMENT  OF  AGRICULTURE 


Volume  IX 


AUGUST,  1920 


No.  8 


Special  Pest  Control  Issue 


SACRAMENTO,  CALIFORNIA 


CONTENTS. 

Pane 
THE  PUNCTURE  VINE    (Tribulus  terrestris) COVER 

THE  BLACK-SCALE  PARASITE,  Aphycus  lounsburyi FRONTISPIECE 

MAKING  A  PURE  SEED  LAW  EFFECTIVE G.  H.  HECKE__     305 

"TERRESTRIAL  TRIBULATION" G.   H.   HECKE__     306 

IMPORTANCE    OF    CALIFORNIA    AS    A    BOXED    APPLE    PRODUCING 

STATE F.   W.    READ 307 

COMING  EVENTS  CAST  THEIR  SHADOWS  BEFORE D.  B.  MACKIE__     309 

THE    LIFE    HISTORY    AND    INTRODUCTION    INTO    CALIFORNIA    OF 
THE   BLACK-SCALE  PARASITE,   Aphycus   lounsburyi  HOW 

: HARRY  S.  SMITH  AND  HAROLD  COMPERE 310 

THE    APPLICATION    OF    VACUUM    FUMIGATION    TO    FRESH    AND 

PACKED   DATES D.    B.    MACKIE__     321 

MISCELLANEOUS      INSECT      AND      FUNGOUS      DISEASES      NEWLY 

REPORTED  FROM  HAWAII HAW.  AGR.  EXP.  STATION__     325 

A  TERMITE  PEST  OF  VINEYARDS R.  L.  NOUGARET__     327 

THE  SPREAD  OF  THE  PUNCTURE  VINE  IN  CALIFORNIA 

ETHELBERT   JOHNSON 330 

ARGENTINE  ANT  CONTROL  FROM  AN  ECONOMIC  STANDPOINT 

A.    F.    SWAIN__     333 

THE   DANGER   OF   INDISCRIMINATE    INTRODUCTION    OF   FOREIGN 

PLANT    VARIETIES I.    WILKANSKT__     339 

A   RECENTLY   DISCOVERED   CITRUS    PEST   IN   CALIFORNIA 

: R.     S.     WOGLUM 341 

SEED     PRODUCTION     OF    THE     CANADA     THISTLE     IN     SOUTHERN 

CALIFORNIA ETHELBERT    JOHNSON__     343 

BEAN  WEEVILS  IN  CALIFORNIA ANDREW  LARSEN     344 

PLANT  QUARANTINE  SERVICE: 
REPORT  FOR  JUNE,   1920 FREDERICK   MASKEW 350 


Si 

s  I 


*  £ 

r    O 


'60 


THE  MONTHLY  BULLETIN 

DEPARTMENT   OF   AGRICULTURE 
STATE  OF  CALIFORNIA 


DEVOTED     TO     AGRICULTURE     IN     ITS     BROADEST    SENSE,     WITH     SPECIAL 

REFERENCE    TO    PLANT    DISEASES,    INSECT    PESTS,    AND 

THEIR    CONTROL. 

to       Sent  free  to  all  citizens  of  the  State  of  California.     Offered  In  exchange  for  bulletins 

C-~y  of  the   Federal   Government  and   experiment   stations,   entomological   and  mycological 

r..->  journals,   agricultural   and   horticultural   papers,    botanical,   biological   and   other  pub- 

^  -  lications  of  a  similar  nature. 

G.  H.  HKCKE,  Director Censor 

C\j    BRONTE  A.  REYNOLDS,  Assistant  Secretary Editor 

Entered   as  second-class  matter   October   6,    1919,   at  the  post  office  at   Sacramento. 
California,  under  the  act  of  June  6,  1900. 


AUGUST,    1920  No. 


MAKING  A  PURE  SEED  LAW  EFFECTIVE. 

Regardless  of  the  expected  legislation  bearing  upon  the  important 
tn  question  of  pure  seeds,  it  is  evident  that  we  must  view  the  matter  from 
o|  certain  angles,  which  may  be  affected  only  indirectly  by  any  regulations 

or  code  of  procedure. 

^       The  most  potent  and  far-reaching  factors  having  direct  bearing  upon 

^  this  important  issue  of  clean,  high-quality  seeds  are  essentially  educa- 

o  tional   and   any   good  results  to   be   had   through  .the   enactment   of 

pertinent  laws  must  of  necessity  be  influenced  in  a  great  degree  by  the 

care  that  has  been  employed  in  preparing  both  the  consumer  and  the 

producer  to  meet  the  conditions  which  will  be  brought  into  action  by 

fel  such  needed  legislation. 

ff  California  at  present  has  no  pure  seed  law.  Such  meritorious  legis- 
jj  lation,  however,  has  been  in  effect  in  other  states  for  some  time  and 
J  notwithstanding  the  faults  and  flaws  that  invariably  crop  out  when 
3  new  codes  and  regulations  are  substituted  for  the  old  order,  the 
8  cumulative  benefits  to  be  had  under  the  operation  of  such  laws  are 
£  readily  appreciated  and  improvement  as  affecting  their  efficiency  is 
<  only  a  matter  of  time  and  progressive  education  work. 

The  great  advantages  to  be  enjoyed  by  a  given  state  from  the  enact- 
ment of  pure  seed  legislation  must  accrue  as  well  from  other  sources 
than  those  merely  having  to  do  with  seed  inspection  and  seed- testing. 
The  farmer  must  of  necessity  be  taught  that  poor  seed  is  dear  at 
any  price. 

Under  such  conditions  the  dealers,  being  confronted  by  more  critical 
buyers  who  decline  to  use  cheap,  and  inferior  seeds,  will  discontinue  or 
discourage  the  sale  of  any  but  a  better  grade,  produced  under  favorable 
conditions  and  ^naranlced  as  to  germination  and  freedom  from  exces- 
sive admixtures  of  noxious  weed  seed. 

Any  seed  laws  which  may  be  placed  on  the  statute  books  in  a  given 
slate  will  have  for  their  primary  object  the  improvement  of  the  quality 


'59916 


306  THE    MONTHLY    BULLETIN. 

of  agricultural  seeds,  but  to  realize  the  greatest  benefits  to  all  con- 
cerned we  must  revert  to  the  source  of  much  of  the  past  difficulty  and 
apply  certain  remedial  measures  on  the  farms  where  the  seeds  are 
produced. 

The  seed  grower  should  understand  that  clean  seeds  reasonably  free 
of  weed  seeds  in  the  end  are  a  matter  of  dollars  and  cents  to  him,  and 
that  the  reputation  of  his  business  will  receive  the  greatest  stimulus 
through  the  exploitation  of  a  guaranteed  product,  exceeding  in  fact  the 
returns  from  any  other  known  source  of  advertising. 

As  an  index  to  the  great  injury  that  misrepresentation  can  work  a 
given  seed  house,  we  will  cite  the  following : 

A  lot  of  seed  (sample  X)  was  purchased  for  alsike  and  timothy 
mixture.  Analysis  showed  it  to  contain  28  different  kinds  of  weed  seeds 
amounting  to  nearly  12  per  cent  by  weight.  This  seed  was  shipped  by 
a  middle-western  seed  house  that  was  guilty  of  many  other  infractions 
of  the  laws  of  common  honesty. 

In  the  absence  of  a  federal  law  it  may  not  be  possible  for  the  state 
to  hold  up  interstate  shipments  such  as  these,  but  we  may  rest  assured 
that  but  few  hard-headed,  thinking  farmers  will  go  back  to  that  seed 
firm  when  they  want  more  alsike  and  timothy. 

Thus  we  may  see  that  the  efficacy  of  any  so-called  seed  laws  that 
may  be  established  depends  in  a  large  measure  upon  the  consistent 
observance  of  many  related  factors  which  may  not  for  purely  mechani- 
cal reasons  be  adequately  covered  by  the  law  as  written. 

To  this  end,  then,  we  should  have : 

(1)  A  wider,  common  knowledge  of  weeds  and  approved  methods 
of  control  and  eradication  to  be  taught  in  the  schools  and  agitated  by 
the  press  through  newspapers  and  farm  journals. 

(2)  The  earnest  cooperation  of  farmers,  seed  dealers  and  seed  pro- 
ducers in  California,  making  for  the  establishment  of  standardized 
grades  of  approved  strains  and  varieties  grown  and  stored  in  California 
under  favorable  conditions. 

(3)  A  radical  departure  from  the  over-colored  extravagant  style  of 
advertising  so-called  phenomenal  varieties  to  be  replaced  by  a  plain, 
honest,  descriptive  statement  as  to  variety,  merits,  etc.     (G.  II.  H.) 


"TERRESTRIAL  TRIBULATION." 

With  the  waning  of  the  1920  summer  season,  the  Department  of 
Agriculture  is  beset  with  queries,  protests  and  anxious  ones,  who  want 
to  know  what  to  do  about  the  novel  and  pernicious  weed  pest  that  is 
playing  havoc  with  their  automobile  tires,  and  one  which,  from  present 
indications,  bids  fair  to  rank  as  a  first-class  dangerous  plant  pest.  The 
offender  is  the  "puncture  vine"  (Tribulus  terrestris),  late  of  the 
Sahara  Desert  and  recorded  by  Pliny  and  others  of  the  elder  historians, 
and  "running  true  to  name" — it  does  puncture! 

This  weed  produces  numerous  prostrate  runners  which  at  frequent 
intervals  bear  burs  consisting  of  clusters  of  five  spiny  nutlets.  At 
maturity  the  nutlets  fall  apart,  always  with  one  spine  pointing  upward. 

By  way  of  explanation,  it  should  be  noted  that  California  is  the 
land  of  "out-of-doors"  and  recent  statistics  show  that  "one  of  every 


THE   MONTHLY   BULLETIN.  307 

seven"  in  the  state  operates  an  automobile.  Also  it  is  notable  in  pass- 
ing that  the  state  is  linked  up  by  splendid  highways,  north,  south,  east, 
and  west,  making  nearly  every  section  easily  and  quickly  available  by 
motor,  which  fact  commercially  has  aided  greatly  in  marketing  perish- 
able fruits  and  vegetables  in  times  of  car  shortage. 

Now  comes  this  Saharan  weed,  which  while  not  having  honorable 
mention  among  the  Biblical  "Plagues  of  Egypt,"  surely  ranks  first  as 
an  enemy  of  automobile  tires  in  California. 

One  outstanding  feature  of  its  dangerous  character  lies  in  the  fact 
that,  while  classed  as  a  plant  fostered  and  nourished  by  arid  desert 
conditions,  it  readily  adapts  itself  and  thrives  in  the  warm,  rich  valley 
lands  of  our  state  wherever  it  has  located. 

A  good  idea  of  the  wide  damage  to  be  accomplished  by  this  pest  may 
be  had  from  the  recently  completed  survey,  which  shows  it  to  be  more 
or  less  widely  distributed  from  Red  Bluff  on  the  north,  through  the 
Sacramento,  San  Joaquin,  Antelope  and  Imperial  valleys,  to  the 
Mexican  border  on  the  south,  which  constitutes  in  fact  the  main  motor 
artery  of  the  state. 

Few  automobile  tires  are  proof  against  its  barbs;  no  bicycle  tire  is 
immune  to  injury;  and  horses  and  live  stock  have  suffered  serious 
injury  as  a  result  of  contact  with  it.  Although  at  this  date  the  range 
of  this  weed  has  been  rapidly  extended,  it  is  possible  still,  by  properly 
supported  action  and  concerted  interest,  to  inaugurate  a  system  for  the 
eradication  of  this  new  pest,  one  of  the  most  unique  in  the  introduced 
plant  history  of  the  state.  (G.  H.  H.) 


THE  IMPORTANCE  OF  CALIFORNIA  AS  A  BOXED  APPLE 
PRODUCING  STATE. 

Few  people  realize  the  importance  of  California  as  a  boxed  apple 
state.  Of  the  total  number  of  ears  shipped  in  1919,  California  ranked 
second,  the  State  of  Washington  being  the  only  one  in  the  Union  to 
exceed  it.  According  to  figures  recently  released  by  the  Federal 
Bureau  of  Markets,  California  was  followed  in  the  number  of  cars 
shipped  in  1919  by  Oregon,  Idaho  and  Colorado  in  the  order  named. 
From  the  State  of  Washington,  the  most  important  boxed  apple  state 
in  the  union,  19,760  cars  of  apples  were  shipped  in  1919,  and  of  this 
number  2257  cars  were  taken  by  New  York  City  and  1366  by  Chicago. 

The  Bureau  of  Markets,  over  a  period  of  years,  has  been  compiling  the 
number  of  carloads  of  the  principal  fruits  and  vegetables  unloaded  at 
the  large  market  centers  of  the  country.  This  information  is  very 
valuable  as  indicative  of  the  consuming  capacity  of  the  larger  terminal 
markets.  The  figures  show  that  California  shipped  4147  cars  in  1919 
and  of  that  number  539  cars  were  unloaded  at  New  York  City,  or  about 
76  per  cent  of  the  California  apples  unloaded  at  the  ten  principal 
market  centers  of  the  United  States.  It  would  seem,  therefore,  that 
NV\v  York  is  by  far  the  most  important  outlet  for  California  stock. 
Chicago  received  66  cars  of  California  apples  in  the  same  year,  Cin- 
cinnati 31,  St.  Louis  24,  Philadelphia  21,  Pittsburgh  16,  and  Kansas 
City  12. 


308 


THE    MONTHLY    BULLETIN. 


The  following  table  abstracted  from  the  Market  Keporter  of  the 
Bureau  of  Markets,  under  date  of  June  5,  1920,  gives  a  very  accurate 
idea  of  the  competition  met  by  California  apples  from  the  other  boxed 
apple  states: 

CARLOADS   OF   APPLES    UNLOADED   AT   TEN    LARGE   CITIES. 
Unloads  by  States  of  Origin  for  Four  Years. 


Originating  state 

New  York 

Philadelphia 

Pittsburgh 

1919 

1918 

1917     1916 

1919 

1918     1917 

1916 

1919     1918     1917 

1916 

Boxed-  Apples. 

83 
2 
187 
2,257 
870 

11 
3,949 

23 

5 
64 
2,243 
561 
124 
2 

3,012 

1 
3 
110 
1,170 
290 
147 
0 

1,721 

0 
6 
45 
1,010 
171 
150 
0 

1,382 

1 

C  1       d 

14           3           a 
32         55         53 
225       450       125 
20         33          9 
18  10          3 
1  !        0           0 

308       546       193 

a 

99 

Idaho      — 

62 
645 
54 
21 
3 

785 

0  ,        0 
139       234 
3          0 

2  j        5 

o  ;      o 

144       239 

3 
334 
3 
3 

0 

343 

Washington    

California 

All   oth°r 

Totals       -      -       -    - 

Originating  State 

Washington 

Cincinnati 

1919 

1918 

1917 

1916 

1919 

1918 

1917     1918 

Boxed  Apples. 
Montana  ._  ,..  .....    

| 

Idaho 

1 
156 

28 

2 
157 
31 

0 
11 

C 
41 
5 

61 

132 

^ 
137 

20            0 
1C4          79 

Washington    .... 

California 

31 
18 

242 

8 
4 

18o 

3  ;         0 
0   ,         2 

127         81 

All   oth°r 

1           0 
188  j     190 

0 

94 

0 

46 

Totals  

Originating  state 

1919 

162 
22 
10 
242 
1,366 

65 
2 

1,953 

Chicago      ' 

St.  Louis                          Kansas  City 

1918 

41 
0 
16 
69 
490 
26 
27 

L 
639 

1917 

107 
6 
17 
163 
785 
52 
116 
2 

1,251 

1916 

1919 

1918  j  1917     1316     1919 

1918     1917 

1916 
31 

Boxed   Apples 
Colorado    .    ._ 

95 
8 
1 
10 
676 
33 
39 
1 

79 

180 

36           6         44 

40        1M 

New  Mexico 

Utah    .  ..    .. 

80 
17 
24 

0 

264 

14 
28 
162 
6 

12 

1 

889 

6 
1S8 
150 
56 

4 

1 

391 

0 
2 
133 

6 
8 

1 

156 

1 
73 
238 
12 
12 
1 

381 

23 

265 

11 
12 
0 

355 

4 
4!) 
188 

1 

2 

38  r 

0 
8 
280 
6 
17 
3 

34f> 

Idaho    ..  

Washington    

Oregon       ..    .. 

California    

All   other   

Totals 

THE   MONTHLY   BULLETIN. 


309 


Originating  State 

Minneapolis 

St.  Paul 

1919 
4 

1918 
10 

1917 
.  1 

1916 
4 

1919 

1918 

1917 

1916 

Boxed  Apples. 
Colorado 

Utah 

| 

Idaho      -      -  

5 
142 
2 
0 
4 

153 

5 
211 
2 
0 
2 

220 

7 
97 
0 
30 
0 

134 

8 
214 
12 
0 
6 

240 

Washington          --    .  --  -—    ...    .. 

145 

1 
1 
4 

160 

4 

! 

183 
5 
57 
12 

258 

158 
10 
0 
0 

172 

Oregon    --.    -    -  _  „„_ 

All  oth°r 

Total*       -            -.    --    -- 

155 

176 

California  is  a  more  important  apple  state  so  far  as  volume  is  con- 
cerned than  is  Oregon,  Idaho,  or  Colorado.  This  fact  emphasizes  the 
importance  of  proper  standardization  work.  If  our  stock  is  going  to 
meet  the  sharp  competition  from  other  states,  it  is  essential  that  apples 
moving  out  of  California  be  graded  strictly  according  to  the  California 
standardization  law,  and  that  every  car  maintain  the  reputation  of  this 
state  for  quality,  grade  and  pack. 

That  California  will  continue  to  be  a  very  important  factor  in  the 
shipment  of  boxed  apples,  is  indicated  by  the  statistics  covering  the 
nonbearing  acreage  in  the  state.  Figures  compiled  by  the  California 
Development  Board  show  that  there  were  690,835  nonbearing  trees  in 
San  Bernardino  County  alone  in  1919,  which  is  more  than  the  total 
number  of  bearing  and  m. lib-firing  trees  in  Santa  Cruz  County  for  the 
same  year.  These  figures  may  be  taken  as  indicative  of  the  nonbearing 
acreage  in  the  southern  California  districts.  Uniform  enforcement  of 
the  apple  standardisation  law  will  prove  beneficial  to  the  industry,  and 
assist  in  obtaining  fair  prices  for  the  large  crops  which  are  bound  to 
come  in  ensuing  seasons.  (F.  W.  R.) 


COMING  EVENTS  CAST  THEIR  SHADOWS  BEFORE. 

The  successful  application  of  vacuum  fumigation  to  the  control  of 
insects  affecting  food  products  marks  a  step  forward  in  matters  of  pest 
control.  While  as  yet  the  field  of  its  possibilities  is  practically 
untouched,  a  list  of  the  products  which  lend  themselves  to  treatment 
by  this  method  covers  such  a  broad  range  that  an  attempt  to  name 
them  would  in  all  probability  place  one  in  the  ranks  of  a  false  prophet. 
In  view  <>f  the  foregoing  it  is  sufficient  1<>  say  that  the  question  as  to 


uum   fumigation 


the   field  of  food  products 
imiir  years  will  answer. 
(D.B.M.) 


THE  MONTHLY  BULLETIN 

CALIFORNIA  STATE   DEPARTMENT  OF  AGRICULTURE 

Vol.    IX  -  AUGUST,    1920 


THE  LIFE-HISTORY  AND  SUCCESSFUL  INTRODUCTION  INTO 

CALIFORNIA  OF  THE  BLACK  SCALE  PARASITE, 

APHYCUS  LOUNSBURYI  HOW.1 

By  HARRY  S.   SMITH*  and  HAROLD  COMPERED 
INTRODUCING  THE   PARASITE    IN    CALIFORNIA. 

The  black  scale  (Saissetia  oleae  Bern.)  which  holds  first  rank  as  an 
insect  pest  in  California,  is  a  good  subject  for  control  by  the  biological 
or  "parasite"  method.  To  our  knowledge,  more  than  thirty  species 
of  insects  are  recorded  as  preying  upon  this  pest  in  various  parts  of  the 
world.  While  some  of  these  parasitic  and  predaceous  insects  are  of 
great  value,  others  are  not  of  much  economic  importance  and  their 
introduction  into  California  would  prove  of  little  benefit.  Professor 
Charles  P.  Lounsbury,  government  entomologist  for  the  Union  of  South 
Africa,  states  in  a  letter  under  date  of  March  30,  1912:  "As  I  have 
written  before,  I  am  firmly  convinced  that  the  black  scale  is  held  down 
in  South  Africa  entirely  through  the  influence  of  parasites.  Its  abun- 
dance on  the  material  collected  for  dispatch  to  California  is  due  merely 
to  the  local  prevalence  of  the  Argentine  ant."  It  is  evident  from 
observations  in  the  past,  that  no  single  parasite  or  predator  controls 
the  black  scale;  instead  there  are  combinations  of  the  different  forms, 
which  by  concerted  action  dominate  the  pest  in  given  localities.  To 
introduce  the  most  effective  species  which  do  not  occur  in  California, 
and  then  to  make  them  attain  their  greatest  efficiency  by  rearing  and 
distributing  them  in  large  numbers  is  one  of  the  undertakings  of  the 
Pest  Control  Service  of  the  California  State  Department  of  Agriculture. 

For  several  years  the  Commission  of  Horticulture,  now  the  State 
Department  of  Agriculture,  has  been  attempting  to  establish  in  Cali- 
fornia, additional  natural  enemies  of  the  black  scale.  In  this  work  we 
have  continually  had  the  active  assistance  of  Dr.  C.  P.  Lounsbury  and 
C.  W.  Mally,  entomologists  for  the  Union  of  South  Africa,  to  whom 
we  are  greatly  indebted.  In  the  summer  of  1912  mention  was  made  of 
rearing  two  hundred  of  what  was  supposedly  Aphycus  loimsburyi  from 
material  received  from  South  Africa.  It  is  now  believed  that  this 
was  a  case  of  mistaken  identity,  another  parasite  being  recorded  under 
this  name.  In  1914,  however,  a  shipment  of  black-scale  material  was 
received  from  Messrs.  Lounsbury  and  Mally,  from  which  we  succeeded 

'The  life-history  investigations  recorded  in  this  paper  are  the  result  of  Mr.  Compere's 
labors.  (H.  S.  S.) 

2Entomologist,  Pest  Control  Service,  California  Department  of  Agriculture,  Sacra- 
mento, Cal. 

'Assistant,  Pest  Control  Service,  California  Department  of  Agriculture,  Alharnbra, 
Cal. 


Tin;  MONTHLY  BULLETIN. 


311 


312  THE    MONTHLY    BULLETIN. 

in  rearing  a  few  specimens  of  what  was  unquestionably  this  species. 
The  material  was  collected  at  Wynberg  and  Sea  Point  near  Cape  Town, 
and  from  the  gardens  of  Cape  Town  itself. 

THE    PARASITES    DETERMINED. 

In  1914  some  of  these  parasites  were  sent  to  P.  H.  Timberlake  for  an 
authentic  determination.  He  replied  that  the  parasites  were  undoubt- 
edly Aphycus  lounsburyi  Howard,  although  fully  twice  as  large  as  the 
types.  The  following  is  transcribed  from  his  letter :  ' '  There  is  a  series 
in  the  U.  S.  National  Museum  which  I  examined  last  winter  and  thought 
at  first  they  might  be  distinct  on  account  of  the  twice  larger  size, 
slightly  exserted  ovipositor,  and  of  the  ocelli  being  in  an  equilateral 
instead  of  a  strongly  acute  triangle.  The  ovipositor  is  not  exserted 
in  the  types,  but  they  are  very  small  specimens  and  wretchedly  pre- 
served. Your  specimens  are  intermediate  as  the  ocelli  are  in  an  acute 
triangle.  On  account  of  the  evident  variation  in  this  species,  I  hope 
you  are  in  a  position  to  preserve  a  good  series  showing  such  variations 
as  I  have  indicated.  Coloration,  however,  is  remarkably  uniform. ' ' 

Owing  to  the  fewness  in  numbers  of  this  parasite  in  the  above- 
mentioned  shipment,  however,  we  did  not  succeed  in  establishing  the 
parasite  in  the  open,  and  it  was  not  until  we  reared  this  same  species 
in  some  numbers  from  material  collected  by  the  late  E.  J.  Vosler  in 
Australia,  and  applied  to  its  propagation  the  recently  developed  method 
of  growing  the  black  scale  on  potato  sprouts,  that  we  were  successful 
in  firmly  establishing  Aphycus  lounsburyi  in  the  citrus  orchards  of 
California. 

DESCRIPTIONS    OF    APHYCUS    LOUNSBURYI. 
The  Adult. 

The  adult  of  Aphycus  lounsburyi  is  very  fantastically  marked  as 
is  strikingly  shown  in  the  frontispiece.  For  a  detailed  technical  descrip- 
tion a  portion  of  P.  H.  Timberlake 's  work  is  herewith  given.1 

Female — Front  and  vertex  apparently  (being  much  shrunken  in  cotypes)  nearly 
three  times  as  long  as  wide;  ocelli  in  an  acute-angled  triangle,  the  posterior  pair 
close  to  the  eye  margin :  untennal  scrobes  broad  and  shallow ;  eyes  nearly  non- 
pubescent.  Antennal  scape  about  one-third  as  wide  as  long,  widest  just  beyond 
the  middle ;  pedicel  as  long  as  the  first  three  funicle  joints  combined ;  first  four 
funicle  joints  of  nearly  equal  length,  wider  than  long  and  hardly  increasing  in 
width,  last  two  joints  considerably  longer  and  wider,  the  sixth  a  trifle  longer  than 
the  fifth,  both  a  little  wider  than  long;  club  oval,  rounded  ;,t  apex,  about  one-third- 
wider  than  the  preceding  joint  and  a  little  longer  than  the  last  four  funicle  joints 
combined.  Wings  uniformly  ciliated;  th:.-  oblique  hairless  streak  but  little  wider 
below,  interrupted,  the  cut-off  portion  separated  from  ih'  basal  hairless  streak  on 
the  posterior  margin  of  the  wing. 

Length:  0.7  mm.  Front  and  vertex  bright  orange  yello\\  :  fatv.  cheeks,  and 
under  parts  pale  yellowish;  mesonotum  dusky  orange-yellow:  concealed  part  of 
the  occiput  and  the  prouotum,  the  metanotum,  propodfiiin.  and  dorsum  of  abdomen 
brown;  collar  of  pronotum  and  tegulae  sordid  whitish;  th-  former  with  a  minute, 
blackish  dot  on  each  corner,  the  latter  witlr  the  posterior  margin  pale  brown. 
Antennal  scape  black  with  a  very  narrow  line  en  upper  margin,  th;*  apex  and 
a  broad  band  on  the  basal  third  of  the  lower  mar-in  white:  base  of  pedicel,  first 
four  funicle  joints  and  club  black;  apical  two-thirds  of  p;-dir.>l.  last  two  funicle 

„  J*rTO£:  ^  S.  Nat.  Mus.  Vol.  50,  page  610.  "Revision  of  the  Genus  Aphycus." 
P.  H.  Timberlake. 


THE   MONTHLY   BULLETIN.  3l3 

joinis  and  some! imes  the  underside  of  the  third  and  fourth  joints  white.  Legs 
pale  yellowish;  middle  tibia-  with  a  pair  of  distinct,  brown  dots  near  base,  another 
pair  at  the  middle,  and  a  narrow,  brown  annulus  at:  the  apex;  hind  tibiae  similar, 
but  the  markings  fainter;  front  tibia*  with  the  apical  annulus  faint  and  the  two 
pair  of  dots  replaced  by  a  large  but  faint  brownish  blotch  on  the  anterior  or 
upper  surface ;  last  joint  of  the  tarsi  faintly  blackish.  Wings  hyaline,  the  veins 
pale  yellowish. 

|  Bedescribed  from  three  females  (cotypes)  in  poor  condition,  reared 
from  Siiis.wtia  oleae  (Bernard),  Cape  Town,  South  Africa  (C.  P.  Louns- 
Imry).  The  fourth  cotype  has  been  lost  by  dropping  from  the  card 
point.] 

"The  following  material  also  examined: 

Seven  females,  one  male  reared  from  the  same  host,  Cape  Colony, 
South  Africa  (C.  P.  Lounsbury),  and  two  females  from  the  same  host 
and  locality  (through  II.  S.  Smith),  California  State  Insectary  No. 
655cp. 

The  females  differ  from  the  types  as  follows: 

!•'< male — Front  and  vertex  varying  from  twice  to  nearly  two  and  one-half  times 
as  lonir  ;,s  wide;  ocelli  in  an  equilateral  triangle,  or  nearly  so,  but  in  three  specimens 
in  more  or  less  acute-angled  triangle,  the  posterior  pair  about  one-fourth  their  own 
diameter  from  eye  margin.  Ovipositor  protruded  about  one-tenth  the  length  of 
abdomen. 

Coloration  nearly  as  in  types  but  the  front,  vertex,  and  mesonotum  uniformly 
dark  orange-yellow,  but  the  dark  parts  nearly  black  instead  of  brown;  dors-urn  of 
abdomen  with  the  lateral  margins  narrowly  whitish  posterior  to  the  vibrissa?  half 
way  to  the  apex,  and  the  anterior  corners  of  the  basal  tergites  invaded  by  the  whitish 
of  the  venter;  tibial  bands  and  dots  heavier  and  blackish  and  with  an  additional  dot 
at  the  knee  joint. 

Length :  1.4  mm. 

l/«/c — Front  and  vertex  a  little  less  than  twice  as  long  as  wide;  ocelli  in  an 
equilateral  triangle.  Antennal  scape  narrower  than  in  the  female  and  the  club 
smaller  or  no  longer  than  the  last  three  funicle  joints  combined.  Wings  as  in 
the  female,  but  the  cut-off  portion  of  the  oblique  hairless  streak  larger  and  con- 
nictinu  with  a  branch  of  the  basal  hairless  streak  on  the  posterior  border  of  wing. 

Length  :    l.o  mm." 

LIFE    HISTORY   NOTES. 

Habits   of   Adult. 

The  adult  parasites  escape  from  circular  exit  holes  cut  through  the 
d(.rsal  region  of  the  shell.  Cutting  the  shell  of  the  older  scales  is  a 
slow  and  laborious  process.  The  parasites  effect  a  small  hole  through 
the  shell  by  biting  out  tiny  pieces  with  their  sharp-pointed  mandibles. 
After  a  hole  is  cut,  it  is  slowly  enlarged  by  cutting  around  the  edges. 
When  the  exits  are  large  enough  to  permit  escape  the  parasites  force 
themselves  out  of  the  old  shells. 

The  adults  are  very  quick  and  active.  AYhon  an  attempt  is  made  to 
catch  them  they  dodge  to  the  underside  of  the  twigs  or  hide  behind  the 
leaves,  something  after  the  manner  of  a  squirrel  in  a  forest  which 
attempts  to  hide  on  the  approach  of  an  enemy.  The  adults  do  not 
readily  take  to  flight  but  depend  on  their  agility  to  escape.  Although 
very  active  and  shy  at  the  approach  of  an  enemy,  AI>IIIICUX  is  a  very 
satisfactory  parasite  to  bundle  in  confinement.  Individuals  confined  in 
viaU  with  sugar  and  water  and  kept  in  a  cold  place,  where  oviposition 
was  prevented,  lived  over  six  weeks  before  they  were  liberated  on 


314  THE   MONTHLY   BULLETIN. 

infested  twigs.  When  confined  in  vials,  the  parasites  need  not  be 
nursed  like  some  of  the  more  delicate  insects.  They  do  not  easily 
become  entangled  in  the  syrup,  and  only  an  occasional  freshening  of 
the  water  is  necessary. 

In  the  field  A.  lounsburyi  does  not  have  a  tendency  to  spread  very 
rapidly  and  must  be  aided  by  man,  a  trait  which  we  consider  to  be 
greatly  in  its  favor.  The  parasites  usually  confine  their  activities  to 
the  individual  trees  in  which  they  are  liberated,  providing  there  is 
a  supply  of  scale  suitable  for  oviposition.  In  many  cases  they  will 
haunt  the  particular  limb  on  which  they  are  first  established.  Unlike 
some  parasites,  this  species  is  particularly  thorough  in  its  work;  if 
in  sufficient  numbers  it  will  parasitize  practically  every  scale  in  the 
area  of  its  abundance.  This  parasite  will  develop  in  any  black  scale 
containing  sufficient  nourishment  to  bring  a  single  larva  to  maturity. 
It  can  commence  work  on  the  small  scales,  beginning  about  the  time 
the  raised  "H"  is  readily  discernible,  and  continues  to  multiply  at 
the  expense  of  the  pest,  until  the  bodies  of  the  parent  scale  have  shriv- 
eled, after  their  eggs  are  laid.  This  is  a  very  decided  advantage,  for  it 

enables  the  parasite  to  propagate,  step- 
ping up  its  abundance  uninterruptedly 
for  almost  the  entire  life  of  the  host, 
which  is  normally  one  year.  In  con- 
trast with  this,  there  are  internal  para- 
sites of  the  black  scale  which  can  con- 
tinue their  activities  for  only  a  very 
limited  period,  because  the  scale  in  its 
FIG.  83.  A.  lounsburyi:  Egg.be-  growth  forms  physical  characteristics 
p0ors?tio(n?PiateTai  SS^JSBUS  which  render  **  invulnerable  to  the  at- 

tack  of  certain  species. 

When  there  is  an  opportunity  for  a  choice,  Aphycus  lounsburyi  will 
select  the  larger  scales  in  preference  to  the  smaller  ones  for  oviposition. 
To  a  certain  extent  this  also  is  a  decided  advantage,  for  it  then  first 
eliminates  the  scales  which  are  likely  to  be  early  egg-bearers,  thus 
prolonging  the  period  in  which  it  can  do  effective  work.  After  the 
scales  commence  egg-laying  this  trait  of  selecting  the  older  individuals 
works  to  a  disadvantage;  it  disrupts  the  host  and  checks  egg-laying, 
but  the  effects  of  the  parasitism  do  not  prevent  the  scale  eggs  which 
have  already  been  deposited  from  hatching,  thus  providing  for  a 
partial  new  generation  to  reinfest  the  trees.  The  effectiveness  of  this 
parasite  can  not  be  judged  merely  by  the  number  of  exit  holes  showing 
in  the  scale.  At  times  the  older  egg-bearing  scale  will  be  parasitized 
to  an  enormous  extent;  but  the  effect  on  the  pest  may  be  slight,  owing 
to  the  fact  that  a  hatch  will  occur  from  the  eggs  already  deposited, 
despite  the  fact  that  the  parent  scales  have  been  destroyed.  This, 
however,  may  work  to  its  advantage  in  another  way,  since  it  provides 
numerous  parasites  for  the  following  generation  of  scales. 

The  work  of  this  parasite  is  characteristic  and  easily  distinguished. 
In  the  advanced  stages  of  parasitism  the  scales  become  bloated,  which 
somewhat  effaces  the  raised  "  H  "  and  their  color  becomes  a  light  amber. 
If  the  scales  are  lifted  from  the  twigs,  the  ventral  tissue  is  seen  to  be 
taut,  membraneous  and  somewhat  translucent.  The  exit  holes  are 


THE    MONTHLY   BULLETIN.  315 

smaller  than  are  those  of  Scutellista  and  usually  there  are  two  or  more 
to  each  scale.  In  the  case  of  A.  lounsburyi  the  exit  holes  only  penetrate 
the  body  cavity  of  the  scale,  while  in  the  case  of  Scutellista  cyanea 
Motsch.  the  exit  holes  penetrate  into  the  egg  cavity. 

As  is  well  known,  many  species  of  insects,  and  particularly  parasitic 
Hymenoptera,  are  parthenogenetic,  i.  e.,  the  eggs  of  the  unfertilized 
females  will  produce  offspring.  Most  insects  which  reproduce  in  this 
way  have  progeny  confined  to  one  sex  only,  that  is,  they  are  either  all 
male  or  all  female.  In  the  case  of  Aphycus  laun-sburyi  only  females 
are  produced  when  the  parent  female  is  unfertilized.  On  the  other 
hand,  if  the  female  becomes  fertilized  the  progeny  is  composed  of  a 
proportion  of  males.  If  the  species  does  not  weaken  by  parthenoge- 
netic reproduction,  it  would  be  a  decided  advantage  if  only  the  females 
are  colonized,  thus  only  increasing  the  individuals  which  are  capable  of 
reproduction.  Observations  extending  over  a  long  period  of  time,  how- 
ever, would  be  necessary  in  order  to  determine  whether  or  not  the 
colonization  of  only  the  females  would  prove  to  be  advantageous.  Cam- 
eron, who  has  made  extensive  studies  in  parthenogenesis,  thinks  that 
this  mode  of  reproduction  involves  a  constitutional  weakness,  fewer  of 
the  parthenogenetic  young  reaching  maturity.  This,  he  suggests,  may 
be  compensated  for  when  the  parthenogenetic  progency  are  all  of  the 
female  sex,  by  the  fact  that  all  those  which  grow  up  are  producers  of 
eggs. 

D.  Sharpe1  after  a  review  of  the  problem  concludes: 

"It  appears  most  probable  that  parthenogenesis  and  the  special  sex 
produced  by  it,  whether  male  or  female,  are  due  to  physiological  con- 
ditions of  which  we  know  little,  and  that  the  species  continue  in  spite 
of  parthenogenesis,  rather  than  profit  by  it. ' ' 

The  studies  of  P.  H.  Timberlake  on  the  subject  of  parthenogenetic 
reproduction  of  the  Encyrtidae  found  in  Hawaii  is  very  pertinent.  The 
following  quotation  is  from  his  work2 : 

"Parthenogenesis  has  also  played  a  large  part  without  much  doubt 
in  helping  the  establishment  of  certain  of  our  immigrant  species.  As 
a  general  rule  it  may  be  stated  quite  confidently  that  all  Encyrtidae 
and  for  that  matter  most,  if  not  all,  Chalcidoidea,  in  so  far  as  their 
habits  have  been  investigated,  are  able  to  reproduce  parthenogenetically 
under  stress  of  necessity.  Probably  most  species  of  Encyrtidae  produce 
only  males  when  the  reproduction  is  parthenogenetic,  and  in  case  of 
the  usual  method  of  reproduction  they  reproduce  in  different  species 
a  variable  proportion  of  both  males  and  females.  Before  studying  the 
habits  of  our  local  species,  I  had  never  verified  the  existence  of  any 
other  method  of  reproduction  among  the  Encyrtidae,  and  was  surprised 
to  find  that  certain  of  our  species  are  regularly  thelyotokus  (i.e.  produce 
only  females)  in  reproduction.  In  Adelencyrtus  odonaspidis,  Blep- 
yrus  mexicanus,  Encyrtus  infelix,  Pauridia  peregrina,  and  Saronotum 
americanum,  thelyotoky  is  the  regular  means  of  reproduction  and  males 
are  rarely  produced,  being  in  fact  entirely  unknown  in  the  case  of 
Adelencyrtus  and  Saronotum.  I  have  reared  Pauridia  through  many 
generations  without  finding  any  males,  and  have  in  fact  seen  but  a 

'Insects:  D.   Sharpe.     Pt.   1,  p.  517. 
"Proc.   Haw.   Entom.   Soc.,   1918,  p.   195. 


316  THE   MONTHLY   BULLETIN. 

single  male,  reared  by  E.  M.  Ehrhorn  several  years  ago.  I  have  like- 
wise reared  Blepyrux  through  several  generations  and  was  able  to  find 
males  of  this  species  only  by  examining  some  vines  at  the  sugar  planters' 
experiment  station  [Hawaii]  at  a  time  when  both  host  and  parasite 
were  unusually  abundant.  Of  Encyrtus  infelix,  I  was  fortunate  enough 
to  rear  a  single  male  in  a  small  series  obtained  in  1916,  and  this  is  the 
only  male  specimen  that  I  have  seen  out  of  the  numerous  specimens 
examined  from  all  parts  of  the  world.  Miss  A.  L.  Embleton  in  her 
work  on  this  species  states  that  the  males  are  exceedingly  rare,  only 
one  occurring  to  about  a  thousand  females.  The  existence  of  this  habit 
of  thelyotoky  is  obviously  a  great  advantage  to  a  species  invading  a 
new  region,  since  it  might  become  established  under  favorable  conditions 
from  a  few  females  or  from  a  single  specimen.  Conversely  the  arrheno- 
tokous  (i.e.  producing  males  only)  habit  of  reproduction  may  act  disad- 
vantageously  before  a  species  is  well  established,  since  the  rapid  dis- 
persal which  usually  takes  place  will  tend  to  increase  the  difficulties 
of  the  sexes  finding  each  other,  and  thus  restrict  the  necessary  fertili- 
zation of  the  female." 

In  the  case  of  Alphycus  lounsburyi  it  was  decided  not  to  try  to  alter 
the  usual  mode  of  reproduction  and  both  males  and  females  were 
liberated.  This  has  not  affected  the  abundance  of  the  parasites  to  any 
great  extent,  the  males  being  very  rarely  met  with  in  the  orchards.  We 
have  never  even  observed  a  pair  mating. 

Oviposition. 

This  parasite  gains  its  superiority  by  means  of  its  singular  method 
of  attack,  which  enables  it  to  overcome  the  protecting  characteristics 
of  the  scale,  and  by  means  of  the  larval  habits  which  permit  its  develop- 
ment in  scale  showing  a  wide  variation  in  size.  The  method  of  attack 
is  specialized  so  as  to  avoid  the  work  of  penetrating  the  tough  leathery 
derm  of  the  scale.  The  long  flexible  ovipositor  is  extended  underneath 
the  scale,  and  then  curved  upward  so  as  to  penetrate  the  soft  ventral 
tissue.  There  is  very  little  work  prior  to  the  insertion  of  the  ovipositor, 
the  female  only  tapping  the  scale  with  her  rapidly-vibrating  antennae. 
The  lateral  margins  around  the  rim  of  the  scale  are  the  points  selected 
for  the  insertion  of  the  ovipositor.  When  oviposition  occurs,  the  para- 
site stands  facing  away  from  the  scale,  with  the  ovopositor  extended 
underneath  the  rim  and  then  curved  upward  so  as  to  penetrate  the 
soft  tissue.  The  act  is  usually  complete  within  thirty  seconds  and  the 
parasite  withdraws.  In  one  scale  an  individual  will  deposit  from  one 
to  twelve  or  more  eggs,  depending  on  the  size  of  the  host.  By  gluing 
scales  to  cover  glasses,  and  then  turning  the  glasses  upside  down  over 
a  cell  containing  a  parasite,  it  is  possible  to  observe  the  act  of  oviposition 
in  detail  under  a  binocular  microscope.  A  strong  light  will  render  the 
ovipositor  and  abdomen  of  the  parasite  transparent,  and  the  interior 
of  the  scale  will  be  rendered  partly  visible,  so  that  the  whole  perform- 
ance can  be  viewed.  When  the  egg  is  forced  from  the  uterus  into  the 
ovipositor  it  is  compressed  to  a  long  cylindrical  form  so  as  to  pass 
through  the  channel  in  the  long  slender  ovipositor.  The  egg  is  hardly 
recognizable  as  it  passes  through  the  ovipositor,  for  so  rapid  and  even 
is  the  movement  that  it  looks  more  like  a  flow  of  quicksilver  than  the 


THE   MONTHLY   BULLETIN.  317 

passage  of  an  egg.  The  forepart  of  the  egg,  which  still  retains  its 
cylindrical  form,  acts  like  a  probe  to  penetrate  some  distance  beyond 
tiif  tip  of  the  ovipositor  into  the  body  of  the  scale.  Suddenly  the  liquid 
contents  of  the  egg  rush  forward,  inflating  the  anterior  portion,  which 
rises  like  a  miniature  balloon  being  inflated.  The  hind  section  of  the 
egg  remains  tube-shaped  after  the  contents  have  rushed  forward.  The 
parasite  then  withdraws  the  ovipositor,  leaving  the  tube  moulded  in 
position,  suporting  the  bulb  or  main  body  at  one  end,  and  the  other 
end  of  the  tube  projecting  through  the  integument  of  the  host  into 
the  outer  air.  "When  the  parasite  withdraws  the  ovipositor,  just  as 
the  end  of  the  stalk  issues,  it  gives  several  vicious  jabs  with  the  oviposi- 
tor. This  may  prove  to  be  the  means  by  which  the  end  of  the  stalk 
is  punctured  so  as  to  make  an  opening  for  the  admittance  of  air. 

The  Egg. 

The  newly  deposited  egg  is  stalked  (fig.  83),  the  bulb  is  elongate 
oval,  translucent  white,  and  with  a  smooth  shining  surface.  The  bulb 
iiir;isiires  .2  mm.  in  length,  and  the  greatest  width  .08  mm.  A  ventral 
ril>  or  stay  extends  about  two-thirds  the  length  of  the  bulb.  The  rib 
appears  to  be  a  prolongation  of  the  stalk.  This  rib  serves  as  a  stay 
which  gives  rigidity  when  the  bulb  is  being  inflated.  Immediately 
after  deposition  the  stalk  becomes  dense  white.  Later  when  the  larva 
hatches  the  stalk  seems  to  function  as  an  air  line,  and  it  then  becomes 
chitinized  and  dark  colored.  The  rib  enters  into  the  construction  of 
the  anal  shield  which  forms  with  the  larva. 

The  ovarian  egg  is  quite  different  in  appearance  from  the  laid  egg. 
It  is  a  double-bodied  affair,  the  two  bulbs  being  divided  by  a  long  neck 
or  constriction.  The  larger  bulb  is  the  main  body  which  later  contains 
the  embryo.  The  smaller  bulb  or  accessory  body  is  an  enlargement 
of  the  neck  which  serves  as  a  reservoir  to  aid  in  the  transformation 
that  takes  place  during  the  passage  of  the  egg  through  the  ovipositor. 
The  ovarian  eggs  of  many  parasites  have  an  accessory  bulb  and  con- 
necting neck  which  is  not  transformed  into  an  air-line  for  the  use  of 
the  larva?.  It  is  supposed  that  this  peculiar  egg  construction  is  for 
the  purpose  of  making  it  possible  to  pass  a  comparatively  large  egg 
through  a  long  slender  ovipositor. 

The  First-Stage  Larva. 

Tin1  newly-hatched  larvae  are  found  suspended  in  the  body  of  the 
scale  by  means  of  a  long  stalk  or  air-line  which  penetrates  the  integu- 
ment of  the  host.  Eggs  and  larvae  can  be  located  by  the  presence  of 
the  stalks,  the  tips  of  which  project  into  the  outer  air. 

The  larva  is  composed  of  thirteen  segments,  exclusive  of  the  head; 
the  five  posterior  segments  being  inclosed  in  an  anal  shield,  which  serves 
to  hold  the  larva  in  intimate  connection  with  the  air-line.  The  average 
sized  newly-hatched  larva1  measures  .5  mm.  in  length,  and  the  greatest 
width  about  .12  mm.  The  head  is  slighly  narrower  than  the  first  seg- 
meut,  the  body  being  of  nearly  uniform  width  throughout.  The  skin  is 
smooth,  white,  and  translucent.  The  anal  shield  and  stalk  are  living 
organisms  in  vital  connection  with  the  larva,  as  suggested  to  be  the  case 
in  Microtcrys  flavus,  which  was  studied  by  Mr.  Timberlake.  In  this 


318  THE    MONTHLY   BULLETIN. 

stage  two  stigmata  are  discernible,  situated  on  a  prolongation  of  the  two 
main  tracheal  trunks  which  places  them  in  contact  with  the  air-line. 
The  two  trunks  are  connected  by  transverse  branches  through  the  first 


FIG.  84.    A.  lounsburyi :  First  stage  larva,  lateral  view,  showing  stalk, 
anal  shield,  and  tracheal  system.      (Original.) 

and  tenth  segments.  On  the  segments  from  two  to  ten  inclusive,  there 
arise  from  the  trunks  simple  undivided  branches,  which  extend  dorsally 
and  ventrally.  Near  the  anterior  end  of  the  trunks  simple  branches 
extend  into  the  head.  Situated  on  the  main  tracheal  trunks  near  the 
junctions  of  the  branches  on  segments  two,  three,  and  four,  the  stigmal 
branches  which  appear  in  the  second  stage  are  beginning  to  form. 

The   Second-Stage   Larva. 

Aside  from  the  increase  in  size,  in  this  stage  there  is  no  great  change 
in  the  general  structure  and  habits  of  the  larva.  The  respiratory 
system  shows  the  most  development,  stigmata  having  formed  on  the 
second,  third,  and  fourth  segments;  and  the  branches  which  arise  from 
the  main  trunks  having  become  so  divided  as  to  form  many  fine 
tracheae. 

The  Third-Stage  Larva. 

Larvae  of  the  third  stage  show  a  marked  change  in  their  structure 
and  habits.  By  this  time  the  parasitic  larvse  have  consumed  the  liquid 
contents  of  the  scale,  the  interior  of  which  now  becomes  a  dry  shell. 


FIQ.  85.     A.  lounsburyi:  Mature  larva,  lateral  aspect.      (Original.) 

There  is  a  change  in  the  method  of  respiration,  the  larvae  no  longer  need- 
ing to  have  the  air  piped  into  the  scale,  for  now  they  can  breathe  air 
direct.  The  intimate  connection  with  the  air-line  is  severed,  freeing  the 


THE    MONTHLY   BULLETIN.  319 

larvae  which  are  now  equipped  with  a  well-developed  trac-heal  system. 
There  is  a  wide  variation  in  the  size  of  the  mature  larvse.  Measurements 
ranged  from  .3  mm.  to  1.7  mm.  in  length,  and  from  .6  mm.  to  .9  mm.  in 
width.  The  body  segments  from  1  to  9  are  larger  and  more  distinct 
than  are  the  succeeding  four  posterior  segments  which  are  not  easily 
defined.  The  body  tapers  towards  the  head  and  rear. 
The  contents  of  the  alimentary  canal  fill  almost  the  entire 
body  cavity.  The  mandibles  are  stout  with  a  broad  base 
and  brownish  in  color.  On  the  main  tracheal  trunks,  in 
addition  to  the  dorsal  and  ventral  branches  on  segments 
2  to  10  inclusive,  there  are  branches  which  extend  to  nine 
A  Fiounsburi  i  •  Pairs  °^  °Pen  stigmata.  The  dorsal  and  ventral,  as  well 
Mandible  of  ma-  as  the  branches  leading  into  the  head,  give  rise  to  numer- 
Si  asvp'ecat~.  ous  fine  tracheae 

The  Pupa. 

The  pupas  which  are  found  in  the  dried  body  cavity  of  the  host 
appear  to  be  naked,  and  as  with  the  larva?  they  are  occasionally  found 
packed  very  tightly.  At  first  they  are  white,  later  they  take  on  the 
color  pattern  of  the  adult. 

Generations. 

The  time  from  egg  to  adult  will  vary  from  twenty-eight  days  to 
three  months,  depending  on  climatic  conditions.  Under  artificial  con- 
ditions in  the  insectary,  twenty-eight  days  was  the  minimum  time  for 
development,  while  in  the  field  during  the  winter  months  this  period 
will  last  for  about  three  months. 

ESTABLISHING    THE    SPECIES    IN    CALIFORNIA. 

Iii  the  fall  of  1919  at  the  Limoneira  Ranch,  Santa  Paula,  California, 
53  lemon  trees  heavily  infested  with  black  scale  were  left  unfumigated 
(through  the  cooperation  of  Messrs.  Teague  and  Culbertson)  in  order 
to  provide  a  propagating  ground  for  Aphycus  lounsburyi.  The  para- 
sites were  first  liberated  in  September.  Liberations  of  Aphycus  fol- 
lowed throughout  the  winter  months.  These  liberations  were  later 
supplemented  by  colonizations  of  Scutellista  cyanea  and  Rhizobius 
r< /ifrnlis  in  order  to  form  a  combination  that  would  insure  a  natural 
control.  The  experiment  proved  satisfactory,  and  at  this  writing  a 
new  area  comprising  10,000  trees  has  been  set  aside  in  an  attempt  to 
duplicate  the  performance  on  a  commercial  scale.  In  this  demonstra- 
tion Aphycus  lounsburyi  accomplished  more  than  did  Scutellista  cyanea 
and  Rhizobius  ventralis  combined.  However,  the  Aphycus  was  given 
the  advantage  both  in  the  number  of  individuals  liberated,  and  by 
making  the  liberations  at  an  earlier  period. 

In  the  city  of  Alhambra  two  other  demonstration  plots  were  selected ; 
one,  comprising  two  and  one-half  acres  set  to  oranges,  and  the  other 
having  100  trees  to  the  plot.  In  both  of  these  plots  the  trees  were 
heavily  infested  with  black  scale  last  fall.  In  these  demonstration 
plots  we  were  not  able  to  make  any  quantity  liberations  until  April. 
The  results  were  not  so  satisfactory,  as  we  were  more  than  six  months 


320  THE   MONTHLY   BULLETIN. 

late  in  getting  our  insects  in  the  field.  This  was  due  to  the  fact  that 
the  insectary  was  invaded  by  the  predaceous  mite,  Pediculoidcs  vcntri- 
cosus  Newport,  which  forced  us  to  destroy  all  of  our  material  and 
make  a  new  start.  Apliycus  is  however  now  breeding  abundantly  in 
both  orchards. 

To  date  about  30,000  Apkycus  lountburyi  have  been  liberated  in  our 
various  demonstration  plots.  They  have  become  acclimated  and  are 
rapidly  increasing,  thus  adding  to  our  fauna  another  beneficial  insect. 

CONCLUSION. 

It  is  very  possible  that  with  the  increase  and  spread  of  Aphycvs 
lounsburyi,  setbacks  will  be  encountered  in  the  way  of  secondary 
parasites,  or  primaries  that  will  adapt  themselves  to  prey  upon  this 
species.  Many  newly-introduced  parasites  have  been  exploited  as 
winners,  and  the  disappointment  which  followed  their  failures  is  pro- 
verbial. Efforts  should  not  cease  howrever  until  the  black  scale  in  Cali- 
fornia is  controlled  by  its  natural  enemies,  or  the  reasons  for  failure 
made  clear.  In  the  light  of  our  present  knowledge,  the  successful 
control  of  the  black  scale  by  the  utilization  of  its  natural  enemies  seems 
to  be  only  a  matter  of  time  and  work.  If  the  beneficial  insects  which 
we  now  possess  can  not  give  the  desired  results  in  our  fight  against  the 
scale,  we  can  introduce  other  species  from  foreign  lands.  At  this  time 
wre  are  engaged  in  trying  to  select  the  most  effective  exotic  forms 
whose  work  will  supplement  that  of  the  parasites  we  already  possess. 

The  black  scale  problem  is  a  serious  one.  A  single  county  in  Cali- 
fornia is  spending  over  three-quarters  of  a  million  dollars  annually 
for  fumigation,  the  major  part  of  which  is  directed  against  this  pest. 
If,  as  is  hoped,  control  can  be  brought  about  by  the  biological  method 
as  was  done  in  the  case  of  the  citrus  mealybug,  it  will  result  in  the 
saving  of  many  hundreds  of  thousands  of  dollars  annually  to  our 
California  citrus  growers.  However,  there  should  be  no  slackening 
in  the  present  methods  of  handling  the  pest  until  the  biological  method 
of  control  is  thoroughly  demonstrated  to  be  practical  on  a  commercial 
scale. 


THE   MONTHLY   BULLETIN. 


321 


THE  APPLICATION  OF  VACUUM  FUMIGATION  TO  FRESH 
AND  PACKED  DATES. 

By   D.    B.    MACKiE.1 

During  the  season  of  1918  reports  were  sent  to  the  State  Department 
of  Agriculture  of  heavy  losses  incurred  in  packed  dates  due  to  the 
inroads  of  certain  storage  insects,  with  the  request  that  the  office  of 
pest  control  investigate  the  matter  and  endeavor  to  formulate  measures 
that  would  give  relief.  In  January,  1919,  the  writer  was  detailed  to 
make  a  preliminary  investigation  and  to  report  on  the  possibility  of 


A  VACUUM  FUMIGATOR. 

FIG.   87.     This  vacuum  fumigator  was  designed  by  the  Pest  Control  Service  of  the 
California  Department  of  Agriculture  for  the  control  of  insects  affecting  dates. 

remedying  conditions.  In  a  conference  the  date  growers  pointed  out 
that  for  some  cause  unknown  to  them  the  packed  dates  became  infested 
and  later,  when  in  the  channels  of  trade,  would  become  so  wormy  that 
purchasers  returned  them  in  disgust,  a  condition  which  in  turn  caused 
merchants  to  decline  to  handle  the  product.  Examination  of  infested 
packages  showed  Ihe  dales  to  hi'  heavily  infested  with  the  larvae  of  ike 

» iiiioii  dried  fruit  pest — Plodia  in-t<'ri>niicl<  l/<i    (Indian  meal  moth) 

and  Sylrann*  Burinamensis  (saw-toothed  grain  beetle).  The  former 
was  decidedly  the  greater  menace  as  the  webs  spun  by  the  larvae  were 
very  much  in  evidence,  thus  making  the  infestation  immediately  mani- 
fest. The  beetle,  being  more  minute,  did  not  cause  so  much  concern, 
though  it  was  equally  if  not  more  numerous  than  the  moth  larvae. 

'Field  Kntomologist,  Pest  Control  Service,  Department  of  Agriculture. 

4—5092 


322  THE    MONTHLY   BULLETIN. 

The  different  growers  and  packers  had  been  fumigating  their  dates 
with  carbon  bisulphide  but  claimed  they  were  not  getting  results. 
An  investigation  proved  that  there  were  a  number  of  factors  which 
contributed  to  the  poor  results  obtained  from  this  procedure.  These 
were,  in  general,  faultily  constructed  fumigation  boxes,  insufficient 
exposure  to  fumigant,  exposure  to  reinfestation  and  conditions  favor- 
ing continuous  infestation  of  packing  houses. 

In  summing  up  the  factors  in  the  equation,  the  problem  resolved 
itself  into  the  development  of  a  process  of  treating  the  finished  product 
in  order  to  preclude  the  possibility  of  further  infestation.  From 
previous  experience  with  vacuum  fumigation  it  seemed  that  this  pro- 
cess offered  a  means  of  guaranteeing  the  destruction  of  the  insects,  but 
its  effect  on  the  dates  was  another  question,  and  one  about  which  the 
writer  himself  was  inclined  to  be  skeptical.  While  some  parties  put 
forth  fantastic  ideas  of  dire  consequences  which  would  attend  treat- 
ment by  this  method,  the  writer's  misgivings  in  this  direction  were 
engendered  by  the  same  beliefs  as  expressed  by  others  less  familiar 
with  fumigants,  i.  e.,  that  the  fruit  would  be  so  impregnated  with  the 
gas  that  it  would  be  difficult  or  impossible  to  remove  the  evidence  of  it. 

To  make  a  long  story  short,  a  homemade  fumigator  was  constructed 
and  a  series  of  experiments  was  made.  In  these  experiments  all 
forms  of  the  moth  and  beetle,  including  eggs,  larvae,  pupa?  and  adults, 
were  subjected  to  treatment.  Confirming  previous  opinion  it  was  found 
that  all  forms  of  both  pests  could  be  killed  by  exposure  to  the  gas  of 
C8'2  (carbon  bisulphide)  used  at  the  rate  of  20  pounds  per  1000  cubic 
feet,  and  injected  at  a  26"  vacuum  for  one  hour.  Adult  beetles  were 
killed  in  five  minutes  exposure,  beetle  larvae  in  thirty  minutes,  beetle 
pupae  in  thirty-five  minutes,  while  the  eggs  required  an  hour.  Moths 
subjected  to  the  same  treatment  succumbed  as  follows:  Adults  six 
minutes,  larvae  forty  minutes,  pupae  forty  minutes,  eggs  sixty  minutes. 
Since  the  above  experiments  were  conducted  it  has  been  proved  that 
with  a  28"  vacuum  100  per  cent  kill  on  moth  eggs  can  be  effected  by 
fifty  minutes,  and  it  is  believed  that  even  this  time  can  be  reduced. 

The  possibility  of  destroying  the  pest  having  been  demonstrated,  it 
remained  to  work  out  a  satisfactory  application  of  treatment.  After  a 
number  of  trials  it  was  found  by  a  mechanical  removal  of  the  gas  and 
a  system  of  air  washing,  i.  e.,  circulating  fresh  air  through  the  mass, 
that  no  trace  of  the  gas  was  left  in  the  product.  As  finally  decided 
upon  the  treatment  is  as  follows : 

1.  Load,  close  and  lock  fumigator. 

2.  Exhaust  air  to  a  26"  mercurial  vacuum. 

3.  Inject  gas  CS2  until  "0"  vacuum  is  reached. 

4.  Expose  to  gas  one  hour. 

5.  Pump  out  gas  to  a  26"  vacuum. 

6.  Open  valves  and  start  pump,  allowing  free  air  to  circulate  through 
the  mass  for  five  minutes. 

Dates  taken  after  being  processed  in  the  above  manner  showed  no 
trace  of  the  gas  even  when  eaten  immediately  upon  removal  from  the 
fumigator,  nor  did  they  produce  any  ill  effects. 


THE    MONTHLY   BULLETIN. 


323 


Being  fully  satisfied  with  the  results  obtained  the  California  Date 
Association  asked  that  the  office  of  pest  control  design  a  commercial 
fumigator  for  their  new  packing  house.  This  machine,  which  is 
shown  in  the  figures,  was  installed  in  September,  1919.  In  October, 
A.  W.  Risher,  of  the  Risher  Date  Gardens,  installed  a  similar  apparatus 
to  handle  his  pack. 

It  was  recommended  by  the  writer  that  all  dates  be  fumigated 
immediately  upon  arrival  at  the  packing  house  and  also  in  the  packed 
boxes  the  last  thing  before  leaving.  The  first  treatment  was  recom- 


How  THE  VACUUM  FUMIGATOR  WORKS. 

FIG.  88.     By  the  vacuum  process,  fumigation  takes  place  in  the  ultimate  container, 
thus  precluding  the  possibility  of  further  infestation  from  an  infested  packing  house. 

mended  in  order  to  be  assured  that  no  infestation  was  brought  into  the 
packing  house  in  dates  coming  from  the  field,  as  it  had  been  noticed 
that  adults  of  the  grain  beetle — Sylvanus  surinamensis — were  found 
on  the  ripe  dates  in  the  field.  This  practice  automatically  prevented  a 
progressive  infestation  from  developing  in  the  packing  house,  and  the 
advisability  of  its  continuance  has  since  been  confirmed.  The  finished 
product,  i.  e.,  both  shredded  date  meat  and  packed  fresh  dates,  is 
subjected  to  fumigation,  the  latter  product  being  treated  as  shown,  the 
last  thing  before  being  placed  in  cartons  for  shipment.  If  success  is 
to  be  measured  by  the  statements  of  those  who  have  applied  this  treat- 
ment to  their  product,  the  results  have  been  highly  gratifying.  Reports 
and  statements  received  by  the  State  Department  of  Agriculture  are  all 
to  the  effect  that  the  treatment  is  an  unqualified  success.  What  is 
considered  as  the  best  evidence  that  can  be  had  to  substantiate  this  is 
the  fact  that  two  other  firms  have  already  approached  the  department 
with  the  intention  of  applying  this  treatment  to  the  coming  season's 
pack. 


324  THE   MONTHLY    BULLETIN. 

In  commenting  upon  the  comparative  value  of  vacuum  fumigation 
and  ordinary  fumigation  methods,  the  following  may  be  said  in  favor 
of  the  former: 

1.  The  time  required  to  treat  the  product  is  reduced  from  36  and  48 
hours  to  1  hour. 

2.  The  killing  power  of  the  fumigant  is  enhanced. 

3.  The  space  occupied  by  apparatus  is  less. 

4.  The  fire  hazard  is  reduced. 

5.  Undesirable  odor  of  gas  is  largely  eliminated. 

6.  Penetration  of  the  fumigant  is  perfect  throughout  the  mass. 

7.  Treatment  can  be  made  right  in  the  packing  house  without  incon- 
venience from  escaping  gas. 

8.  It  provides  for  fumigation  in  the  ultimate  container.    The  gas  can 
be  injected  and  removed  mechanically. 

The  possibility  of  treating  the  finished  product  as  a  trade  practice  is 
a  thing  which  is  not  often  appreciated  at  its  true  value.  To  be  able 
to  say  that  a  product  is  free  from  insect  pests  is  worth  more  to  the 
average  fruit  packer  than  is  generally  believed.  In  regard  to  dates  it 
is  a  very  difficult  matter  to  fumigate  by  the  old  method  in  the  ultimate 
container  (candy  boxes),  as  the  gas  is  dependent  upon  its  own  weight 
to  permeate  the  parts  of  the  pack.  Provided  it  do.es  enter  each  closed 
box,  it  then  becomes  difficult  of  removal.  By  the  vacuum  method  the 
gas  can  be  injected  and  removed  mechanically,  leaving  the  product 
Free  from  any  residue  gas. 

Another  matter,  of  less  significance  generally  but  nevertheless  of 
great  importance  in  special  cases — it  is  a  custom  to  use  in  high  class 
candy  boxes  more  or  less  gilt  lettering  either  on  trade  marks  or  else- 
where. Long  exposure  to  CS2  will  inevitably  discolor  all  gilding. 
The  shorter  exposure  required  under  vacuum  does  not  entail  the  dan- 
ger from  discoloration  as  in  the  longer  method  by  evaporation  at 
atmospheric  pressure. 

It  has  been  a  common  belief  that  the  costs  incident  to  the  construc- 
tion of  a  vacuum  fumigator  are  exorbitant.  As  a  matter  of  fact  this 
is  not  the  case.  One  of  the  fumigators  installed  in  the  Coachella  Valley, 
which  is  illustrated,  cost — including  pump,  motor,  fumigating  drum 
and  installation— less  than  $600. 

The  operation  of  a  vacuum  fumigator  using  CS2  is  very  simple  and 
does  not  require  an  especially  trained  operator.  The  apparatus  at  the 
Risher  Date  Gardens  is  operated  entirely  by  Mrs.  Risher,  who  received 
only  fifteen  minutes  instruction  in  the  operation  by  the  writer. 

In  summarizing  it  may  be  stated  that  an  entire  season  has  passed 
since  this  control  problem  was  presented  to  the  Department  of  Agri- 
culture, two  fumigators  have  been  operating  continuously,  and  accord- 
ing to  the  packers  operating  them  they  are  an  unqualified  success. 

This  successful  application  of  vacuum  fumigation  to  dates  marks  a 
decided  step  forward  in  the  treatment  of  food  products  for  purposes  of 
pest  control.  In  the  field  of  dried  fruit  industries  alone  there  lies  an 
immense  opportunity  for  the  application  of  this  method. 


THE    MONTHLY   BULLETIN.  325 

MISCELLANEOUS  INSECT  AND  FUNGOUS  DISEASES. 

Newly  Reported  From  Hawaii.1 

Diseasi  x  not  hi  tin  Ha  r<  ported  in  Hawaii.  So  far  as  is  indicated  by 
the  available  records,  the  following  diseases  observed  during  the  year 
have  not  been  previously  reported  in  Hawaii : 

Algaroba  (Prosopis  chilensis).  Black  spots  of  pods.  Pycnidial 
fungus  similar  to  organism  Phonm  musae  n.  sp.  associated  with 
black  spot  of  Chinese  bananas.  Pycnospores  appendaged,  meas- 
uring 10.9  by  7.3  microns.  Pycnidia  145  to  165  microns,  ostiole 
readily  seen,  15  microns  in  diameter. 

Bean  (Pliaseolus  sp.).  Rust  (Uromyces  appendiculatus) ,  leaf  and 
pod  spot  (Isariopsis  griseola). 

Brassica  (Sinapis  cernua),  "kin  choy."  White  rust  (Albugo  Can- 
dida). 

Cactus,  prickly  pear  (Opuntia  sp.).    Blight  (Diplodia,  opuntiae[f] ). 

Carrot  (Daucus  carota).     Root  knot  due  to  nematodes. 

Cotton  (Gossypium  sp.).    Anthracnose  (Glomerella  gossypii). 

Eggplant  (Solwnum  melongena).  Leaf  spot  (PhyUosticta  hortorum), 
root  knot  due  to  nematodes. 

Litchi  (Litchi  chincmis).  Leaf  blight  due  to  ascigerous  fungus  of 
Glomerella  type. 

I 'CM  M ut  (Arachis  hypogea).  Wilt  (Sclerotium  rolfsii),  leaf  spot 
(Septogloeum  arachidis?). 

Rice  (Oryza  sativa).  Blast  (Piricularia  grisea),  stem  and  root 
disease  associated  with  Pythium  sp.  ( ?). 

Roselle  (Hibiscus  sabdariffa) .  Root  disease  associated  with  Fusarium 
radicicola. 

Sorghum  (Sorghum  sp.).    Smut  (Ustilago  reilianaf) . 

Tobacco  (Nicotiana  tabaaun).  ]\fosaic  disease,  root  knot  due  to 
nematodes,  vascular  disease,  Granville  wilt  (?). 

Tomato  (Lycopersicum  esculentum) .  Mite  disease  (mite  apparently 
the  same  as  potato  mite. 

Potato  (Solanum  tuberosum ) .  Early  blight  (Alternaria  solani) ,  com- 
mon scab  (Actin-omyces  chromogenus) ,  tuber  rot  (Fusarium  coeru- 
leum),  and  tuber  galls  due  to  nematodes. 

Turnip  (Brassica  campestris) .  Root  scab  (Rhizoctonia  sp.),  white 
rust  (Albugo  Candida). 

Miscellaneous  fungous  and  insect  pests.  Among  other  diseases  and 
pests  observed  during  the  year  were  the  following: 

Avocado    (Persea  gratissima).     Blight   (Glomerella  cingulata). 

Banana  (Musa  cavendishii) .    Red  spider. 

Bean  (Phaseolus  sp.).  Anthracnose  (Glomerella  (Gloeosporium) 
lindemuthicma) . 

Cabbage  (Brassica  oleracea).  Webworm  (Hellula  undalis),  green 
cabbage  worm  (Pontia  rapav),  bac-terial  soft  rot. 


'Report  of  Hawaiian  Agi'k'ulturul  Experiment  Station  for  1918   (1919). 


32'6  THE   MONTHLY   BULLETIN. 

Coffee  (Coffea  sp.)     Sooty  leaf  mold  (Capnodium  sp.?). 

Corn  (Zea  mays').  Leafhopper  (Peregrinu  maidis}  ;  motling  dis- 
ease similar  to  yellow  stripe  disease  of  corn,  cause  undetermined. 

Guava  (Psidium  guajava) .    Eusseting  due  to  red  spider. 

Litchi  (Litchi  chinensis).     Erinose,  Eriophyes  sp. 

Mango  (Mangiferasp.}.    Blight  (Glomerella  cingulata). 

Monterey  cypress  (Cupressus  macrocarpa).    Roaches. 

Onion  (Allium  cepa).     Thrips. 

Potato  (Solanum  tuberosum).  Tuber  moth  (Phlhorimcca  opercul- 
ella),  wilt  (Fusarium  oxysporum},  tuber  rot  (Fusarium  oxysponim 
and  F.  radicicola),  and  rosette  (Ehizoctonia  sp.). 

Pineapple  (Bromelw  sp.).  Bud  rot  (cause?),  wilts  of  several  types 
apparently  not  caused  by  parasitic  organisms  but  suggesting  mal- 
nutrition. 

Taro  (Colocasia  sp.) .  Root  rots  of  several  forms,  a  specie  of  Pythium 
(?)  associated  with  most  common  type. 

Tomato  (Lycopersicum  esculentum}.  Blight  (Phytoplithora  infes- 
tans}. 


THE   MONTHLY   BULLETIN. 


327 


A  TERMITE  PEST  OF  VINEYARDS. 

By  R.  L.  NouGARKT,1  Sacramento,  California. 

Recently,  termites,  commonly  called  white  ants,  have  been  discov- 
ered in  the  vineyard  districts  of  Merced  County  attacking  young  vines.2 
It  is  seldom  that  this  insect  attacks  living  tissue,  but  in  the  case  of 
•  in  jury  to  young  vines,  it  is  due  to  the  great  number  of  termites  orig- 
inating from  pieces  of  stalk  of  the  Arundo  donax,  used  in  setting  out 
vineyards  instead  of  the  small  pieces  of  laths  or  other  wooden  sticks 
commonly  used  for  this  purpose. 

The  Arundo  donax  is  a  plant  quite  different  from  bamboo,  but  in  its 
appearance  and  the  manner  of  growth  it  resembles  the  latter.  It  grows 
as  a  long  stalk,  with  long  narrow  leaves  produced  at  each  joint,  and 


A  SOURCE  OF  TERMITE  DANG 


FIG.  89.  The  hollow- jointed  canes  of  this  plant  (Arundo  donax)  furnish 
shelter  for  the  "white  ants"  or  termites,  which  later  caused  damage  to 
vineyards  in  the  Merced  District. 

attains  a  height  of  fourteen  to  sixteen  feet.  It  is  grown  in  rows  along 
ditches  to  serve  as  windbreaks.  It  is  a  very  vigorous  grower,  requiring 
no  cultural  care,3  very  little  attention  is  given  to  the  windbreak  once 
growing  well.  Broken  stalks  are  allowed  to  lie  where  they  fall  •  they  dry 
out  and  being  hollow  in  the  center,  provide  an  excellent  breeding  place 
for  the  termites  above  mentioned. 


3In    charge,    Viticultural    Service,    California   Department   of   Agriculture. 

"Arthur  E.  Beers,  Horticultural  Commissioner  of  Merced  County,  first  noticed 
these  conditions  and  brought  them  to  the  notice  of  the  writer.  The  following  notes 
are  the  results  of  an  investigation  which  followed. 

'New  shoots  every  year  sprout  up  from  the  roots.  These  keep  reaching  out  Into 
new  soil  and  the  canes  increase  in  numbers  very  rapidly.  After  a  short  period  of 
years,  a  single  row  of  roots  set  out  along  a  ditch  bank  has  become  of  considerable 
width  and  forms  an  excellent  windbreak  quite  difficult  to  penetrate. 


328 


THE   MONTHLY    BULLETIN. 


This  species  of  termite  has  been  determined  by  Nathan  Banks  as  the 
Reticuliterm.es  hesperus,  a  very  common  species  species  throughout 
California;  in  view  of  this  fact  it  will  be 
necessary  to  more  carefully  clean  up  the 
rows  of  windbreaks  of  all  broken  pieces 
of  cane  if  this  insect  is  to  be  kept  under 
control  than  were  it  a  species  introduced 
from  Europe  with  the  plant,  and  the  lat- 
ter being  a  special  host.  If  this  is  not 
done  these  termites  may  become  a  serious 
pest  not  only  in  respect  to  young  vine- 
yards but  to  dwellings  and  wherever  lum- 
ber is  used. 

The  injury  to  the  young  vines  is  caused 
by  the  termites  breeding  in  great  numbers 
in  the  pieces  of  stalk  and  leaving  the 
latter,  due  to  overcrowding.  They  find 
their  way  to  the  young  vines  and  attack 
them  under  ground,  gaining  entrance  at 
the  lower  end  where  the  roots  originate. 
They  bore  up  through  the  pithy  substance 
of  the  vine,  gnawing  through  the  nodes 
and  destroying  the  pithy  fibre  and  attack- 
ing the  live  tissue  surrounding  it.  In 
this  way  a  long,  empty  tubular  space  is 
f.  produced  throughout  the  whole  length  of 
perus,  is  widely  distributed  on  the  the  trunk,  in  which  mold  and  decav  is 

Pacific      Slope.      (Snyder     and  ,     ,    ,  •    ,  -,.  ,.  ,, 

Banks.)    u.  s.  Nat.  MUS.  started  by  moisture  ascending  from  the 

soil. 


DISTRIBUTION    MAP. 
FIG.  90.     As  will  be  noted 


LIFE     HISTORY    AND     HABITS. 

According  to  Nathan  Banks  Reticulitermes  hesperus  is  a  new  species. 
As  we  have  no  data  at  hand  relating  to  the  biology  and  habits  of  this 
species  we  will  give  under  this  heading  only  some  general  characteristics 
common  to  this  group  of  insects. 

The  termites  though  commonly  called  white  ants  belong  to  a  different 
entomological  order  than  the  latter.  They  have  however  some  analogy 
to  the  ant  in  the  social  habits  of  both.  In  the  colonies  of  termites  are 
found  three  distinct  fonns — the  worker  and  the  soldier,  which  are 
wingless  and  are  found  in  the  colony  at  all  times,  and  the  sexual  form, 
comprising  both  male  and  female.  They  appear  for  a  short  period  of 
time  only  and  have  wings  while  swarming,  which  they  drop  shortly 
afterwards.  From  the  sexual  females  is  produced  the  egg-laying  queen 
who  provides  the  eggs  for  the  colony.  The  workers  and  soldiers  are 
undeveloped  individuals  of  the  sexual  form.  They  attend  to  all  the 
duties  of  the  colony,  besides  which  the  soldier  defends  it  from  intruders. 
The  winged  termites  are  migrants  capable  of  becoming  founders  of  new 
colonies.  These,  however,  are  generally  formed  by  the  splitting  up  of 
old  ones,  when  these  become  too  populated  or  the  extending  of  their 
galleries  reaches  more  favorable  conditions  of  food.  Termites  feed  on 
decaying  vegetable  matter,  moistened  wood  and  even  bore  their  galleries 
into  timbers.  Living  fibrous  tissues  are  rarely  attacked. 


THE    MONTHLY    BULLETIN. 


329 


TKK.MITK    DAMAI;;;   TO   YOUNG   GRAPEVINE. 

FIG.  91.  Damage  to  younw  wrap,  vines  in  the  Merced  District  by  the 'termite. 
Reticvlitermea  ftoaperttt.  The  colonies,  propagating  in  the  canes,  utilized  to  stake 
young  vines,  destroy  the  pith. 


330  THE   MONTHLY   BULLETIN. 

Control. 

As  may  be  observed  in  figure  91  showing  young  vines  split  open  longi- 
tudinally, the  soft  substance  or  marrow  of  the  vine  has  been  destroyed, 
the  harder  fibrous  section  or  node  eaten  through,  the  cavities  containing 
the  marrow  widened  by  the  walls  being  attacked,  and  finally  one  long 
tubular  space  left  from  the  top  of  the  trunk  down  its  whole  length  with 
an  opening  into  the  soil,  but  with  a  thin  obstruction  left  at  the  very 
top  so  that  sunlight  can  not  penetrate  into  the  empty  space  occupied 
by  the  colony.  The  workers  and  soldiers  can  not  endure  the  rays  of 
the  sun,  their  soft  bodies  rapidly  shriveling  up.  Vines  thus  infested 
have  the  heart  of  the  trunk  exposed  to  the  moisture  of  the  soil,  which 
will  cause  mold  to  form,  followed  by  decay.  If  such  vines  are  not 
killed  during  the  early  stage  of  their  growth,  they  will  more  than  likely 
have  become  weak  and  nonprofitable  at  a  time  they  should  be  in  their 
prime.  It  is  therefore  best  to  pull  them  up,  dig  a  good  sized  hole 
where  they  stood,  scatter  the  earth  taken  from  it  out  upon  the  surface 
of  the  ground  so  that  any  termites  that  might  be  mixed  with  it  will 
be  exposed  to  the  sun  rays  and  thus  destroyed.  The  following  spring 
it  will  be  safe  to  plant  another  healthy  rooted  vine  in  the  same  place; 
and  above  all,  avoid  using  pieces  of  stalk  of  the  plant  which  is  an 
excellent  host  for  the  termites  to  stake  out  the  new  vineyard  or  as 
props  to  tie  up  young  vines.  Clean  up  the  windbreaks  and  burn  all 
pieces  of  dead  stalks;  by  so  doing  future  serious  infestations  may  be 
forestalled. 

Damage   Not  Yet  Serious. 

Although  as  yet  no  very  serious  damage  ha*s  been  reported  of  vines 
dying,  still  this  condition  is  apt  to  interfere  seriously  with  the  growth 
of  the  vines  and  the  future  crop  production,  even  if  the  vines  are  not 
killed  outright. 

It  has  also  been  noticed  on  several  occasions,  when  the  pieces  of 
stalks  set  out  temporarily  in  planting  the  vineyard  have  been  replaced 
with  permanent  redwood  stakes,  that  the  latter  have  been  attacked 
by  the  termites.  It  is  easy  to  understand  that  if  these  conditions  pre- 
vail to  any  extent  necessitating  restaking  part  of  the  vineyard,  the  loss 
caused  by  the  termites  might  amount  to  a  considerable  sum. 


THE  SPREAD  OF  THE  PUNCTURE  VINE  IN  CALIFORNIA. 

By  ETHELBERT  JOHNSON,'   Sacramento,   California. 

The  puncture  vine,  Tribulus  terrestris,  was  probably  introduced  into 
the  United  States  from  the  Mediterranean  region  in  ships'  ballast.  Its 
advent  into  California  is  directly  traceable  to  the  railroads.  In  the 
hot  dry  climate  and  fertile  soils  of  our  interior  valleys,  the  plant 
seems  to  have  found  conditions  even  more  favorable  to  its  growth 
than  its  native  habitat  on  the  borders  of  the  Sahara  Desert. 

The  earliest  report  of  the  puncture  vine  in  California  was  in  1903, 
when  it  was  found  growing  along  a  railway  bank  at  Port  Los  Angeles. 
In  1908  it  was  found  in  abundance  in  the  Southern  Pacific  yards  at 
Colton,  and  was  also  collected  near  San  Bernardino.  In  1912  it  was 

'Technical  assistant,  California  Department  of  Agriculture. 


THE   MONTHLY   BULLETIN. 


331 


reported  as  a  troublesome  weed  in  the  vicinity  of  Bakersfield.  It  has 
now  spread  over  a  large  area  in  the  upper  San  Joaquin  Valley  and  is 
found  in  a  nearly  unbroken  line  along  the  railroads  northward  to  San 
Joaquin  County.  In  the  Sacramento  Valley,  it  has  been  found  at 
Woodland,  Durham  and  Marysville,  and  is  reported  as  widely  spread 
along  the  railroads  in  Tehama  County. 

S'outh  of  Tehachapi,  the  puncture  vine  is  found  from  the  Mexican 
border  through  the  Imperial  and  Coachella  valleys  to  the  coastward 


THE  "PUNCTURE  VINE"  (Tribulus  terrestris). 

FIG.  92.  This  weed  produces  numerous  prostrate  runners 
which  at  frequent  intervals  bear  burs  consisting  of  clusters 
of  five  spiny  nutlets.  At  maturity  the  nutlets  fall  apart, 
always  with  one  spine  pointing  upward.  The  burs  shown 
in  the  illustration  are  actual  size. 

vsillcys  of  Riverside,  San  Bernardino,  Los  Angeles  and  Orange  counties. 

From  the  rapidity  of  its  spread  in  the  upper  San  Joaquin  Valley  in 
the  last  ten  years,  it  is  to  be  expected  that  the  pest  will  continue  to 
extend  its  limits  from  these  newer  centers  of  infestation  until  something 
is  done  to  check  it. 

The  plant  produces  numerous  prostrate  stems  which  frequently  grow 
to  a  length  of  eight  feet.  At  every  joint  is  produced  a  number  of  burs, 
usually  five,  which  separate  as  soon  as  they  mature.  Each  bur  possesses 
two  or  more  sharp  spines  about  the  size  of  carpet  tacks,  so  disposed 
that  however  the  bur  may  fall,  one  spine  will  always  point  upward. 
These  spines  will  pierce  an  automobile  tire  the  tread  of  which  is  some- 
what worn,  and  will  readily  puncture  a  bicycle  tire. 


332 


THE    MONTHLY   BULLETIN. 


The  Aveed  threatens  not  only  the  motorist,  but  the  farmer  as  well, 
.since  it  invades  pastures,  hayfields  and  cultivated  crops,  and  is  capable 
of  inflicting  severe  injuries  upon  all  classes  of  stock,  especially  horses, 
by  piercing  the  frog  of  the  foot,  Intensive  farming  practices  will  keep 


I'ISTKIBUTION  OF  THE  "PUNCTURE  VINE"    (Tribulus  terrestris)    IN  CALIFOKNIA. 


cultivated  lands  free  from  weeds,  but  the  real  problem  of  the  puncture 
vme  is  its  control  in  waste  land  and  along  roadsides  and  railroad  rights 
t  is  important  that  the  people  of  the  state  be  alive  to  the 
urgent  necessity  of  curbing  the  spread  of  this  vicious  pest  to  the  end 
that  they  may  demand  that  adequate  measures  be  taken  to  check  it 


THE    MONTHLY   BULLETIN. 


333 


ARGENTINE  ANT  CONTROL  FROM  AN  ECONOMIC 
STANDPOINT. 

A.  F.   SWAIN,*  Riverside,  California. 
INTRODUCTION. 

During  the  past  few  years  the  Argentine  ant  (Iridomynncx  humilis 
Mayr)  has  become  a  very  serious  pest  in  many  of  the  southern  Cali- 
fornia citrus  districts.  In  fact  from  a  financial  standpoint,  where 
uncontrolled  it  is  one  of  the  most  serious  of  our  insect  enemies.  It  was 
only  a  dozen  years  ago  that  it  was  first  observed  in  California.  In  1910 
Woodworth2  stated  in  regard  to  the  southern  California  infestation: 

''Recently  discovered  colonies  in  and  about  Los  Angeles  place  that 
district  well  toward  the  front  in  the  amount  of  infested  territory,  and 


FIG.    94.     Materials  used   in   setting  out   "poison   bait"    for   the   Argentine   ant. 

five  small  colonies3  in  the  neighborhood  of  Riverside  complete  the 
enumeration  of  the  points  of  distribution  at  present  known  and 
mapped." 

At  the  present  time  there  are  several  hundred  acres,  or  more  cor- 
rectly a  few  thousand  acres,  in  the  Riverside  district  that  are  infested. 
This  past  season  some  500  acres  belonging  to  the  National  Orange 
Company  alone  were  heavily  infested.  The  degree  of  infestation  may 
be  realized  when  it  is  known  that  when  one  walked  through  an  orchard 

"Entomologist.    National    Orange    Company,    Riverside,    Cal. 

"Woodworth,  C.  W.  The  Control  of  the  Argentine  Ant.  Calif.  Exp.  Station  Bull. 
207,  October,  1910. 

'The  italics  are  the  writer's,   not  Professor  Woodworth's. 


334  THE   MONTHLY   BULLETIN. 

and  accidentally  brushed  against  the  leaves  of  a  tree,  hundreds  of  ants 
rushed  onto  him.  Inspection  work  was  not  the  most  pleasant  of  occu- 
pations because  of  the  abundance  of  the  ants.  Men  working  in  the 
orchards  had  to  keep  their  lunches  in  watertight  containers,  placed  in 
irrigation  flumes,  to  keep  the  ants  out.  One  day  some  men  tried  the 
plan  of  hanging  their  lunch  baskets  on  a  wire  midway  between  two 
trees,  but  to  no  avail  for  the  ants  crawled  out  the  wire  and  down  into 
their  baskets. 

CONTROL. 

"When  the  writer  took  charge  of  the  insect  control  operations  for  this 
company  in  August  of  last  year,  the  ants  were  extremely  abundant  and 
troublesome.  Men  had  threatened  to  leave  because  of  the  presence  of 
the  ants  in  their  homes.  Consequently  it  was  decided  to  inaugurate 
control  measures.  Poison  was  made  up  according  to  the  "Improved 
Barber  formula"  as  recommended  by  Woglum  for  use  under  the  low 
humidity  conditions  of  the  interior  sections  of  southern  California. 
During  the  fall  months  (October  and  November)  approximately  20,000 
trees  were  treated,  and  in  the  latter  part  of  November  some  13,000 
of  these  were  retreated.  During  March  and  April  of  this  year  another 
33,000  were  treated.  Several  containers  were  studied  and  tried  before 
the  one  finally  used  was  chosen.  The  two-ounce  spice  cans  as  used  by 
Borden  and  Woglum  were  tried  and  found  to  be  satisfactory  for  hold- 
ing the  syrup,  but  because  of  the  initial  cost  ($17.50  per  thousand) 
and  the  labor  necessary  to  waterproof  them  with  paraffin  and  to  punch 
holes  in  them  they  were  discarded.  Paper  bags  were  found  unsatis- 
factory because  of  the  fact  that  in  a  short  time  they  split  at  the  seams. 
The  writer  obtained  a  few  two-ounce  spice  cans  made  from  heavy  card- 
board, with  tin  tops  and  bottoms,  which  were  very  satisfactory.  Paraf- 
fining them  was  unnecessary  as  they  were  waterproof  already,  but  the 
necessity  of  punching  holes  in  them  and  their  initial  cost  ($22.50  per 
thousand)  caused  them  to  be  discarded.  The  container  finally  adopted 
consisted  of  a  pressed  paper  drinking  cup.  These  cups  were  made  of 
one  circular  piece  of  paraffined  paper  pressed  into  shape.  There  being 
no  seams  to  burst  and  their  cheapness  (slightly  less  than  $5.75  per 
thousand)  together  with  the  ease  of  handling  a  goodly  supply  caused 
their  final  adoption.  These  cups  fit  one  into  another,  so  that  the 
operator  could  carry  a  large  number  of  them  conveniently.  In  fact 
each  operator  would  start  out  with  a  box  of  100,  the  box  being 
3"  x  3"  x  18".  Their  main  drawback  was  that  they  were  open  at  the  top, 
allowing  rain  to  enter  them  during  the  winter.  If  they  had  to  be 
refilled  in  the  spring  a  large  percentage  of  them  had  to  be  replaced. 
However,  their  slight  cost  permitted  this  with  a  less  expenditure 
than  with  the  spice  cans. 

The  operation  as  carried  on  was  as  follows:  Each  operator  was  sup- 
plied with  100  cups  in  a  box,  a  small  amount  of  excelsior  in  one  pocket, 
a  few  f-inch  roofing  nails  in  another,  a  small  hammer,  and  a  can  of 
poisoned  syrup.  The  cans  used  to  carry  the  syrup  were  the  ordinary 
gallon  kerosene  cans,  in  which  a  long  spout  (about  fifteen  inches  in 
length  and  a  quarter  of  an  inch  in  diameter)  led  from  the  bottom 
rather  than  from  the  top  of  the  can.  This  permitted  the  cups  to  be 
filled  easily  after  having  been  tacked  onto  the  trees.  This  gallon  can 


THE    MONTHLY   BULLETIN.  335 

would  hold  enough  syrup  to  fill  one  hundred  cups.  The  first  operation 
was  to  place  a  few  strands  of  excelsior  in  a  cup,  the  top  was  then 
folded  over  longitudinally,  a  nail  put  through  it  near  the  top,  the  cup 
tacked  to  the  trunk  of  a  tree,  and  then  filled  with  the  syrup  up  to  the 
nail.  In  this  manner  each  operator  after  a  day's  practice  was  able 
to  place  from  40  to  50  cups  an  hour,  or  350  to  400  a  day.  Labor  cost 
$3  per  day,  resulting  in  less  than  .01  per  tree.  The  cost  of  the  cups, 
nails  and  excelsior  was  about  .0065  per  tree.  As  made  up  the  poisoned 
syrup  cost  approximately  80^  per  gallon,  or  .008  per  tree.  The  complete 
cost  of  treating  53,000  trees  and  refilling  cups  on  13,000  of  them  was 
$1,428,  or  about  .024  each. 

The  syrup  was  made  up  in  20-gallon  quantities  according  to  the  fol- 
lowing formula: 

12J  gallons  water,  in  which  was  dissolved 

2  ounces  of  tartaric  acid.     This  was  heated  to  almost  the  boiling  point  and 

then 
100  pounds  of  sugar  was  added  slowly  and  well  stirred  until  dissolved,   and 

then  allowed  to  boil  for  one  hour.     After  this  cooled 
<;   ounces   of  sodium   arsenite,   dissolved   in   a   few   pints  of  lukewarm  distilled 

water,   were   added,   and   finally 
'_'<)   pounds   of  strained    honey   and 
4  minces  scdium  Ix-nxnate,   previously  dissolved   in  a   little  water,  were  stirred 

into  tho  solution. 

It  was  found  after  some  experimenting  that  a  cheap  grade  of  honey, 
the  socalled  "baker's  honey,"  was  as  satisfactory  as  a  higher  grade 
product,  provided  that  it  was  boiled  and  strained  properly.  This  neces- 
sitated a  slight  additional  labor,  but  the  difference  in  price  between  this 
low  grade  honey  at  lO^f  a  pound  and  the  higher  grade  product  at  22^ 
to  25^  a  pound  more  than  repaid  the  additional  labor  cost.  If  the 
honey  used  is  not  strained,  it  will  cause  a  crystalization  in  the  syrup. 
In  fact  it  is  necessary  to  boil  it  several  minutes  before  straining  to 
prevent  crystalization.  It  was  further  found  that  at  least  one  hour's 
boiling  of  the  syrup  was  necessary  to  insure  against  a  souring  of  the 
product  later.  Even  this  long  a  boiling  of  quantities  of  one  or  two 
gallons  was  not  a  complete  insurance,  and  even  the  adding  of  a  small 
amount  of  benzoate  of  soda  did  not  overcome  it  entirely.  It  is  probably 
due  to  the  great  amount  of  heat  necessary  to  cook  such  large  quantities 
as  20  to  25  gallon  lots  that  prevented  later  souring.  One  other  point 
brought  out  by  this  work  was  the  fact  that  sodium  arsenite  known  as 
"technically  pure"  gave  as  good  results  in  the  field  as  the  "chemically 
pure."  However,  the  writer  would  not  care  to  recommend  the  use  of 
this  product,  nor  would  he  use  it  if  "chemically  pure"  sodium  arsenite 
is  available. 

RESULTS. 

As  stated  above,  20,000  trees  were  treated  during  the  months  of 
October  and  November,  and  33,000  during  March  and  April.  All 
orchards  (with  one  exception  noted  later)  were  fumigated  during  the 
season  of  September  to  January.  The  treatment  last  fall  followed 
immediately  after  fumigation.  At  that  time,  therefore,  there  was  a 
minimum  of  natural  feed  for  the  ants  inasmuch  as  the  scale  had  been 
cleaned  up  by  the  fumigation  (through  the  whole  acreage  there  was 
.100  per  cent  cleanup  on  the  scales  present).  Furthermore  at  that 


336  THE    MONTHLY   BULLETIN. 

season  of  the  year  aphids  are  very  scarce  in  this  section,  and  could  not 
furnish  feed  for  them.  Within  two  weeks  after  the  poison  was  placed 
on  the  trees  no  ants  could  be  found,  nor  did  they  return  at  any  time 
during  winter,  even  when  there  were  several  very  warm  days.  At  the 
present  writing,  a  few  ants  can  be  found  here  and  there,  but  for  all 
practical  purposes  the  cleanup  has  been  100  per  cent  efficient. 
Furthermore,  the  present  season  is  far  enough  along  now  so  that 
another  treatment  will  not  be  necessary.  This  shows  that  one  treat- 
ment is  sufficient  for  at  least  two  seasons.  That  brings  the  cost  to  only 
.012  per  tree  per  year. 

Barber1  recommends  the  spring  as  the  best  time  for  treatment  for  it 
is  with  the  advent  of  warm  weather  that  the  large  winter  colonies  are 
broken  up  and,  according  to  him,  at  that  time  food  is  at  its  minimum. 
Woglum  and  Borden2  recommend  either  a  spring  or  a  fall  treatment  - 
in  the  spring  time  because  of  the  breaking  up  of  the  winter  colonies, 
and  in  the  fall  because  the  cold  nights  make  the  ants  more  or  less  slug- 
gish. The  writer  observed  that  during  May  this  year  the  majority  of 
the  winter  colonies  were  being  broken  up.  However,  in  the  spring  time 
there  is  always  present  a  greater  or  less  amount  of  weeds  and  grass  in 
orchards,  because  of  the  fact  that  the  orchards  are  not  cultivated 
thoroughly  during  the  winter.  These  weeds  and  grasses  harbor  aphids. 
which  in  turn  furnish  food  for  the  ants.  In  the  fall  aphids  are  not  at 
all  abundant  in  or  about  orchards,  and  this,  together  with  the  sluggish- 
ness of  the  ants  due  to  the  cool  nights,  make  this  season  of  the  year 
the  most  satisfactory  for  attempting  control.  The  results  of  poison 
placed  cut  during  March  and  April  this  year  are  not  so  striking  as 
that  placed  during  November  and  October  of  last  year.  However,  the 
results  are  good,  and  while  the  writer  feels  that  the  best  time  for  con- 
trol is  during  the  fall  months,  if  for  any  reason  this  is  not  possible,  the 
spring  will  do  very  well. 

SOME     ECONOMIC    CONSIDERATIONS. 

It  is  without  question  possible  to  so  reduce  the  numbers  of  ants  in 
orchards  that  their  presence  is  unnoticeable,  as  has  been  proven  by  the 
work  of  Woglum  and  Borden3  at  Uplands,  California,  and  by  the 
writer's  work  here  reported.  However,  in  spite  of  the  work  by  Woglum 
and  Borden  which  has  been  brought  before  the  citrus  growers  of  the 
.south,  it  is  still  believed  by  many  orchardists  that  the  Argentine  ant 
is  of  little  or  no  importance  to  them.  To  tell  an  orchardist  that  the  ants 
protect  mealybugs  and  scale  insects  is  all  well  and  good,  but  the  average 
man  does  not  pay  much  attention  to  it.  Show  him  a  comprehensive 
demonstration  as  that  of  Woglum  and  Borden  in  Uplands  or  of  the 
writer  in  Riverside,  and  then  give  him  actual  figures  as  to  costs  and 
money  saved,  and  he  will  be  awakened. 

In  1917  a  period  of  extreme  heat  had  such  disastrous  results  on  the 
black  scale  in  this  locality  that  even  now  there  is  but  very  little  pres- 
ent, and  fumigation  for  this  pest  has  been  practically  abandoned  for 
the  past  three  seasons.  However,  the  soft  brown  scale  survived  the  heat 
better  and  at  present  wherever  the  Argentine  ant  is  present  in  this 

'Barber,  ER.  The  Argentine  Ant.  Distribution  and  Control  in  the  United 
States.  U.  S.  Dept.  Agri.  Bull.  377,  August,  1916. 

Woglum,  R  S.  and  Borden,  A.  D.  A  Comprehensive  Demonstration  of  Argentine 
Ant  Control.  The  California  Citrograph,  Vol.  4,  No.  6,  r,  147  April  1919 

"Op.  tit. 


THE    MONTHLY    BULLETIN.  337 

locality  the  soft  brown  scale  is  abundant.  Quayle1  wrote  concerning 
this  insect,  that  "while  seldom  occurring  in  injurious  numbers  over  an 
entire  orchard.  |  it  \  often  severely  infests  an  occasional  tree  or  portion 
of  a  tree,  but  the  infestation  is  usually  of  short  duration,  due,  in  most 
cases,  to  tlie  efficient  work  c;f  one  or  two  parasites."  This  is  very  true 
outside  the  territory  of  the  Argentine  ant.  but  it  is  decidedly  not  so  in 
the  Riverside  district  at  the  present  time.  It  was  necessary  for  the 
writer  to  have-  over  200  acres  fumigated  last  fall  for  this  pest  alone, 
and  undoubtedly  due  entirely  to  the  Argentine  ant.  Here  is  an  item  of 
over  $6,000  to  be  charged  against  the  Argentine  ant,  not  taking  into 
account  the  loss  in  value  of  fruit  through  a  lowering  of  its  grade  due 
to  smut.  This  one  item  of  expense,  the  fumigation  of  200  acres,  more 
than  covers  three  times  the  entire  cost  of  ant  treatment  of  over  500 
acres. 

Whether  the  ants  could  have  been  so  efficiently  controlled  with  the 
scale  present  in  large  numbers  was  a  question  in  the  writer's  mind  until 
a  short  time  ago.  As  it  so  happened  there  was  one  ten-acre  block  of 
Washington  navel  trees  which  were  heavily  infested  last  fall  with  both 
the  s  )i't  In-own  scale  and  the  Argentine  ant.  Due  to  pressure  of  other 
work  this  block  was  not  fumigated,  although  the  ant  poison  was  placed 
on  the  trees.  \o  inspection  of  the  block  was  made  until  a  few  weeks  ago, 
and  the  writer  was  both  surprised  and  pleased  to  find  that  the  ants  were 
entirely  cleaned  up,  and  furthermore  a  half  hour's  search  did  not  bring 
to  view  a  single  living  specimen  of  the  soft  brown  scale.  Another  block 
of  Washington  navels  adjoining  some  of  this  company's  property  was 
heavily  infested  last  year  with  both  the  ant  and  the  soft  brown  scale. 
Some  poison  was  given  the  owner  who  placed  it  on  the  trees  last 
November.  The  results  there  are  the  same  as  in  the  orchard  just 
mentioned.  This  proved  conclusively  to  the  writer  that  the  ants  could 
be  controlled  even  when  the  soft  brown  scale  was  abundant,  and  ant 
control  resulted  in  scale  control.  Which  is  cheaper,  .024ff  per  tree  for 
ant  poison,  or  MOr  t»  4(V  per  tree  for  fumigation,  with  ants  still  present 
after  the  later  process? 

Woglum  and  Horden-  pointed  out  how  the  Citrophilus  mealybug  was 
controlled  in  the  Cplands  district  through  the  control  of  the  ants.  A 
portion  of  a  1  .Vac re  block  of  Washington  navels  belonging  to  this  com- 
pany has  been  infested  to  a  small  degree  with  this  mealybug  for  the 
past  two  01-  three  years.  Kadi  year  it  has  spread  slightly.  However, 
ant  poison  was  placed  on  the  trees  last  fall,  and  twice  bands 
which  were  on  the  trunks  of  the  trees  were  removed  and  washed  in 
kerosene  and  the  tree  trunks  washed  with  15  per  cent  kerosene  emul- 
sion with  the  result  that  at  present  not  more  than  a  couple  of  dozen 
trees  are  infested  with  the  mealybug,  and  on  these  only  a  very  few 
c:mld  be  found.  A  lemon  orchard  adjoining  this  block  has  been  treated 
for  the  mealybug  regularly  every  few  weeks,  the  bands  being  removed 
and  washed  and  the  tree  trunks  scrubbed  with  kerosene  emulsion,  yet 
the  mealybug  is  very  abundant.  No  attempt  has  been  made  there  to 
control  the  ants. 

There  is  another  point  to  be  considered  on  which  no  previous  investi- 
gator has  seemed  to  t:;uch  in  regard  to  the  Argentine  ant,  that  is,  its 

'Quayl.-.    II.   .1.      Citrus   Fruit   [BMcU.      Calif.    K\i>.    Station  Bull.  214,  May.   1911. 
-Op.  cit. 


338  THE    MONTHLY   BULLETIN. 

effect  on  labor.  It  is  true  that  the  ants  have  no  "sting"  nor  do  they 
"bite"  one,  but  it  is  rather  annoying  to  have  them  crawling  over  one's 
face  and  hands  and  down  his  collar,  and  feeding  on  his  lunch.  And 
this  is  exactly  what  they  do.  To  such  men  as  pickers  and  pruners  they 
are  a  very  serious  pest.  Considerable  loss  is  realized  through  the  inef- 
ficiency of  labor  due  to  the  presence  of  the  ants — both  in  lost  time 
fighting  them  off,  and  in  lost  time  breaking  in  new  men  to  replace 
those  who  refuse  to  work  under  such  conditions.  A  very  conservative 
estimate  of  the  loss  of  efficiency  on  this  company's  orchards  is  15  per 
cent.  That  means  if  it  takes  20  men  10  days  to  pick  the  fruit  on  a 
given  block  where  the  ants  are  not  present,  it  will  take  over  11  days  to 
pick;  the  same  block  if  the  ants  are  at  all  abundant.  At  $3  a  day  per 
man,  this  means  an  additional  cost  of  about  $70  a  day.  With  a  picking 
crew  of  20  men  working  six  months  of  the  year,  the  additional  cost  for 
labor  due  to  a  loss  of  15  per  cent  efficiency  amounts  to  approximately 
$1,000.  Add  to  this  20  more  men  working  on  the  average  of  200  days 
a  year  in  various  orchard  operations,  as  hoeing  weeds,  irrigating,  prun- 
ing, and  so  forth,  and  an  additional  cost  of  about  $1,400  is  realized. 
There  is  then  a  loss  of  about  $2,400  a  year  due  to  the  effect  of  the  ants 
on  labor.  Ant  control  cost  $1,400  and  is  good  for  at  least  two  years  and 
possibly  three,  which  means  a  saving  in  the  one  item  of  labor  alone  of 
over  $1,500  a  year.  Consequently  if  the  relationship  of  the  ants  to  the 
scale  insects  and  mealybugs  is  not  considered,  the  cost  of  treatment  is 
more  than  warranted  by  the  saving  in  labor  costs. 

CONCLUSION. 

It  has  been  demonstrated  that  the  Argentine  ant  can  be  controlled 
under  citrus  orchard  conditions  in  southern  California,  this  costing 
less  than  2^  per  tree  per  year,  possibly  only  1J^  per  tree  per  year. 
The  ant  is  a  prime  factor  in  the  Riverside  district  in  the  abundance  of 
the  soft  brown  scale  and  has  necessitated  the  great  expense  of  fumiga- 
tion, which  is  several  times  greater  than  the  cost  of  ant  control.  It  is 
also  a  prime  factor  in  the  abundance  and  spread  of  the  Citrophilus 
mealybug,  which  is  potentially  a  very  serious  orchard  pest.  The  loss  in 
efficiency  of  labor  due  to  the  ant  is  greater  than  the  cost  of  ant  control. 


THE   MONTHLY   BULLETIN.  339 

THE  DANGER  OF  INDISCRIMINATE  INTRODUCTION  OF 
FOREIGN  PLANT  VARIETIES. 

By  I.  WiLKANSKY,1  Jerusalem,  Palestine. 

The  introduction  of  foreign  varieties  of  plants  used  to  be  considered 
by  our  farmers  in  Palestine  as  a  sign  of  progress  and  scientific  manage- 
ment. Everybody  tried  to  introduce  something  foreign,  seldom  stopping 
to  consider  whether  it  was  worth  while  or  whether  the  foreign  was 
not  inferior  to  the  native  variety. 

I  am  going  to  cite  a  few  facts  which  will  show  how  extremely  cautious 
one  has  to  be  in  introducing  foreign  varieties  of  plants. 

Our  first  European  experts  having  rather  naturally  assumed  a 
superior,  disdainful  attitude  towards  our  native  agriculture  have  also 
treated  with  contempt  the  native  varieties  which  have  grown  in  Pales- 
tine for  thousands  of  years  and  have  thoroughly  adapted  themselves  to 
the  local  physical  factors. 

One  of  their  first  acts  was  to  introduce  French  varieties  of  olives, 
though  we  have  had  five  good  native  varieties  of  oil  producing  olives. 
The  Jewish  farmers  of  Palestine  saw  something  quite  revolutionary 
about  it — the  trees  looked  different  and  their  fruit  was  large — and 
they  proceeded  to  imitate  and  grafted  their  trees  to  the  new,  imported 
varieties.  But  before  the  trees  had  come  to  bearing  they  were  found 
to  be  infested  with  boring  beetles  (Bimatismus  villosus  and  Phloeotri- 
lus  olcae]  and  the  olive  fly  (Bactrocera  IDacus]  oleae).  Only  the  for- 
eign varieties  were  infested ;  the  native  ones  were  free  from  these  pests. 
The  growers  had  to  dehead  trees  as  old  as  twenty  years  or  more  and 
regraft  them  to  the  native  varieties. 

At  present  our  Jewish  olive  growers  carefully  avoid  taking  grafting 
stock  from  our  olive  groves,  in  spite  of  the  fact  that  our  olive  groves 
are  much  better  than  the  groves  of  the  native  fellahin  (peasants)  for 
fear  that  they  may  stumble  by  mistake  upon  some  imported,  foreign 
stock.  Grafting  stock  is  therefore  taken  from  the  groves  of  the  native 
fellahin  in  which  only  native  varieties  of  the  olive  may  be  found. 

In  the  experimental  farm,  Ben  Shemen,  of  which  I  have  been  in 
charge,  I  had  the  following  happen  to  me.  In  my  olive  nursery  I 
insisted  upon  using  grafting  stock  derived  exclusively  from  the  famous 
olive  forests  of  Lydda  and  Ramleh,  in  the  foothills  of  Judea.  The 
varieties  of  that  district  are  called  Rumi,  hinting  that  they  were 
planted  by  the  Crusaders.  Later  however  I  discovered  that  a  portion  of 
the  nursery  was  grafted  with  stock  which  was  brought  by  a  Jewish 
farmer  from  one  of  our  colonies  where  French  varieties  of  the  olives 
were  still  grown.  A  grove  was  planted  with  stock  from  this  nursery. 
Up  to  the  bearing  age  of  the  trees  nothing  uncommon  was  observed  in 
the  growth  of  the  trees,  but  on  the  eighth  year,  the  olive  fly  broke  out 
in  the  grove. 

Prior  to  this  I  never  had  observed  the  olive  fly  in  Palestine.  But  I 
remembered  it  very  well  since  a  tour  in  Italy.  There  I  saw  hordes  and 
hordes  of  flies  covering  the  piles  of  olives  gathered  in  their  storehouses. 
In  the  restaurants  when  olives  were  served,  my  companion,  an  Italian 

'Director  of  Agriculture  of  the  Zionist  Commisson,  Jerusalem,  Palestine. 


340  THE    MONTHLY   BULLETIN. 

horticulturist,  would  cut  the  olives  open  to  show  me  the  galleries  and 
labyrinths  made  by  the  fly  in  the  meat  of  the  olive.  Olive  after  olive 
he  would  cut  open  and  every  one  of  them  would  invariably  show  these 
characteristic  labyrinths.  I  knew  that  in  Italy  the  olive  fly  was  con- 
sidered one  of  the  greatest  pests  known  and  that  the  best  of  Italian  ento- 
mologists were  devising  means  to  combat  it.  Prof.  Berlese  was  dis- 
tributing at  that  time  in  the  olive  groves  of  Italy  baits  of  molasses  and 
arsenic,  placing  the  pots  among  the  branches  of  the  trees. 

And  here  I  had  the  same  "problem"  before  me.  Was  it  possible 
that  I  failed  to  observe  this  pest  in  Palestine  until  it  affected  my  own 
trees?  I  immediately  proceeded  to  inspect  carefully  the  old  native 
groves  located  within  a  mile  or  so  of  the  farm  in  my  charge.  Not  on 
one  tree  grown  on  those  thousands  of  acres  have  I  discovered  a  trace 
of  the  pest.  I  showed  olives  affected  with  the  fly  to  the  owners  of 
those  groves — no  one  of  them  had  ever  seen  it  before.  I  visited  our 
Jewish  colonies — none  of  the  trees  grafted  to  native  varieties  was 
affected.  Only  in  one  small  grove  I  found  the  olive  fly.  The  owner 
wanted  to  produce  a  Provence  variety  and  he  did  not  graft  his  trees 
to  a  native  variety. 

Nor  do  the  boring  insect  Himatisms  inllosus,  Phloeotribus  scarbc- 
oides  and  Hylesinus  oleiperda  attack  the  native  Palestinian  varieties, 
the  wood  of  the  native  varieties  being  firm  and  hard  while  that  of  the 
French  varieties  is  tender  and  soft. 

And  if  we  compare  the  yields  of  the  native  varieties  with  those  of 
the  foreign  ones,  we  shall  see  that  they  are  inferior  neither  in  quality 
nor  in  quantity. 

It  is  obvious,  then,  that  in  this  case  it  was  inadvisable  to  introduce 
foreign  varieties.  But  even  if  the  foreign  varieties  were  superior,  it 
is  still  very  questionable  whether  it  would  pay  to  sacrifice  the  great 
resistance  and  peculiar  adaptation  of  the  native  varieties  for  the  sake 
of  superiority  in  other  respects. 

Therefore  extreme  vigilance  and  careful  judgment  should  be  exercised 
when  it  is  proposed  to  introduce  foreign  varieties.  In  general  it  is 
best  to  leave  the  matter  of  introduction  from  foreign  countries  in  the 
hands  of  specialists  and  experts  on  the  staff  of  introduction  gardens, 
they  being  best  qualified  to  exercise  all  the  vigilance  and  judgment 
required. 


THE   MONTHLY   BULLETIN.  341 

A  RECENTLY  DISCOVERED  CITRUS  PEST,  PLATYNOTA 
TINCTANA  (WALK.)  IN  CALIFORNIA. 

L5y   R.   S.   WOGIATM,  U.   S.   Bureau  of  Entomology. 
INJURY    TO    ORANGES    BY    WORMS. 

Injury  to  oranges  from  short  burrows  in  the  rinds,  frequently  the 
forerunner  of  decay,  is  familiar  to  most  packing-house  managers  and  to 
many  growers  in  southern  California.  These  burrows  or  tunnels,  each 
with  a  small  exit,  for  the  most  part  open  but  sometimes  partly  filled 
with  web.  have  generally  been  attributed  to  the  orange  tortrix  (Tur- 
//•/./•  ci(rana').  Xo  other  tortricid  larva  appears  to  have  been  recorded 
as  injuring  citrus  in  this  state,  although  several  species  have  been 
reported  as  minor  pests  of  the  orange  in  Florida. 

REARING    WORK    AT    ALHAMBRA. 

In  1915,  some  oranges  and  lemons  attacked  by  lepidopterous  larva? 
were  collected  at  Alhambra  and  placed  in  rearing  cages.  The  moths 
which  emerged  differed  greatly  from  the  orange  tortrix  (T.  citrana) 
and  proved  to  be  identical  with  specimens  reared  in  July,  1913,  from 
larvae  collected  in  citrus  nursery  stock  at  Whittier.  This  same  species 
did  considerable  damage  during  the  spring  of  1915  to  the  young  growth 
of  citrus  nursery  stock  on  the  laboratory  grounds  at  Pasadena  by  rolling 
up  or  binding  together  and  destroying  the  tender  bud  leaves.  Speci- 
men.-, of  these  moths  submitted  at  that  time  to  Dr.  H.  G.  Dyar  of  the 
I'.  S.  National  Museum,  were  identified  as  Platynota  sp.,  and  more 
recently  August  Busck  determined  material  from  the  same  lot  as  /'/«///- 
in/fa  tinctana  Walker. 

OUTBREAK   OF   ORANGE   WORMS    IN   1916. 

A  severe  outbreak  of  orange  worms  occurred  during  the  autumn 
of  1916  in  the  Alhambra-Pasadena  district,  causing  a  heavy  loss  of 
fruit.  This  outbreak  was  reported  by  Quayle1  who  attributed  the 
injury  solely  to  the  orange  tortrix.  The  writer,  however,  made  a  care- 
ful study  of  the  situation  at  that  time  and  collected  many  larva-  and 
infested  fruit  in  orchards  suffering  most  severely.  The  moths  which 
emerged  proved  to  be  partly  Tortrix  citrana  and  partly  Plat])  not  a  tine- 
tana.  More  recently  (1919)  reports  of  severe  tortrix  injury  in  Orange 
County  led  to  an  investigation  of  fruit  conditions  in  packing  houses 
and  orchards  with  the  result  of  proving  the  damage  to  be  due  to  both 
species  of  orange  worms.  The  orange  tortrix,  however,  predominated 
at  the  time  of  the  inspection  in  August. 

SIMILARITY    TO    PLATYNOTA. 

This  pest  appears  to  be  identical  with  specimens  of  Platynota  which 
were  highly  destructive  to  carnations,  asters  and  chrysanthemums  at 
Hollywood  in  1913  by  destroying  the  buds,  webbing  together  the  leaves 
or  eating  into  the  stalk.  The  moths  have  frequently  been  observed 

'California   Citrograph,    April,    1918,   p.    133. 

239916 


342  THE   MONTHLY   BULLETIN. 

about  lights  both  at  Pasadena  and  Alhambra  at  times  when  a  careful 
search  of  the  nearest  citrus  trees  failed  to  show  evidence  of  infestation. 
In  a  letter  enumerating  the  known  food-plants  of  this  insect  August 
Busck  states  that  "the  species  of  Platynota  are  all  general  feeders  and 
that  orange  is  only  one  of  the  food-plants  of  Platynota,  tinctana  Walker. 
In  fact  I  have  it  in  the  collection  from  various  greenhouse  plants  and 
from  cotton  and  carnations." 

DESCRIPTIONS. 

The  adult — The  adult  is  a  rather  small  moth,  with  pointed  head  and 
somewhat  heavy  forewings  which,  when  folded,  form  a  rooflike  ridge 
over  the  body.  The  females  are  a  variable  grayish-brown  with  a  faint 
indication  of  an  oblique  darker  colored  band  on  each  wing.  They  aver- 
age slightly  less  than  half-an-inch  long  with  folded  wings.  The  males 
are  fully  one-third  smaller  than  the  females,  somewhat  darker  and  the 
surface  of  the  forewings  is  roughened  with  elevated  tufts  and  ridges 
of  coarse  scales.  This  tufted  and  ridged  condition  of  the  male  fore- 
wings,  their  darker  color  and  conspicuously  smaller  size,  readily  dis- 
tinguishes the  adult  of  the  orange  webworm  from  the  cinnamon-colored 
smooth-scaled,  V-banded  orange  tortrix. 

The  egg — The  eggs  are  deposited  upon  the  surface  of  leaves  in 
patches  of  transparent  yellowish-green  color,  each  egg  overlapping 
another  after  the  manner  characteristic  of  this  group  of  insects. 

The  larva — The  larvae  are  dark  colored  with  a  conspicuously  black 
head.  This  coloration  readily  separates  them  from  the  greenish-white 
larva?  of  orange  tortrix. 

HABITS   OF  THE    LARVA. 

When  present  on  fruit-laden  orange  trees  the  larvas  are  usually  found 
webbed  within  old  dried  leaves  or  fallen  flower  petals  close  to  the  fruit, 
or  even  webbed  against  the  fruit  itself.  Not  infrequently  they  lurk  in 
the  protection  of  touching  fruit,  especially  if  in  large  clusters.  The 
fruit  is  damaged  through  puncturing  of  the  rind.  The  orange  web- 
worm  does  not  appear  to  confine  itself  within  the  burrows  in  the  fruit 
so  closely  as  does  the  orange  tortrix,  nor  does  its  burrow  usually  pene- 
trate so  deeply  toward  the  rag. 

PARASITES  OF  ORANGE  WEBWORM. 

The  worm  and  pupa  are  highly  parasitized  even  as  is  the  orange 
tortrix.  At  least  three  distinct  species  of  hymenoptera  have  been 
reared  from  the  Iarva3  and  pupa3,  including  two  internal  species  and 
one  ectoparasite.  These  parasites  appear  able  to  control  the  pest  except 
on  occasional  years.  An  example  of  the  rapidity  with  which  natural 
control  may  occur  is  well  shown  by  the  history  of  an  infested  orchard 
in  Orange  County.  Worms  had  been  abundant  in  the  spring  and  were 
numerous  in  August.  Specimens  collected  during  this  latter  month 
were  heavily  parasitized.  An  examination  the  following  May  failed 
to  reveal  a  single  worm  and  evidence  of  injury  to  the  new  crop  of  fruit 
was  difficult  to  find. 


THE   MONTHLY   BULLETIN.  343 

DISTRIBUTION. 

Mr.  Busck  gives  the  distribution  as  the  west  coast  of  the  United 
States  extending  down  into  Mexico  and  Central  America. 

The  apparent  wide  distribution  of  this  newly  recorded  orange  pest 
and  its  diversity  of  hosts  portends  a  recurrence  of  its  attacks  to  oranges 
from  time  to  time  even  as  has  been  the  history  of  the  orange  tortrix. 
The  writer's  studies,  however,  lead  him  to  believe  that  the  pest  will 
prove  less  injurious  than  the  tortrix. 


SEED  PRODUCTION  OF  THE  CANADA  THISTLE  IN 
SOUTHERN  CALIFORNIA. 

By  ETHELBERT  JOHNSON/  Sacramento,  California. 

The  Canada  thistle,  Cirsium  arvense,  is  a  weed  pest  with  an  exceed- 
ingly bad  reputation  which  is  not  yet  widely  distributed  over  California. 
Patches  of  it  are  found,  however,  in  Orange  and  San  Bernardino  coun- 


FIG.  95.  Heads  of  Canada  thistle,  in  the  order  of  their  stages  of  development ; 
Top  row,  the  female;  bottom  row,  the  male.  (N.  Z.  Journ.  Agric.) 

ties,  and  at  least  one  infestation  has  been  reported  from  Los  Angeles 
County.  It  is  also  more  or  less  abundant  in  Humboldt  and  other 
northern  counties. 

In  the  south,  the  Canada  thistle  produces  seed  rarely  or  not  at  all. 
Unlike  other  thistles,  the  Canada  thistle  produces  two  types  of  flowers, 
male  and  female,  which  are  nearly  always  borne  on  separate  plants. 
The  male  heads  are  nearly  round,  short  and  stumpy,  and  more  or  less 

'Technical   Assistant,   California  Department  of  Agriculture,   Sacramento,  Cal. 


344  THE   MONTHLY    BULLETIN. 

flattened  near  the  top.  The  female  heads  are  somewhat  elongated,  and 
narrowed  in  at  the  top.  For  seed  to  be  formed  it  is  necessary  for  the 
pollen  to  be  carried  by  insects  from  the  male  to  the  female  plants.  Even 
then  seed  is  frequently  not  formed,  since  hot  weather  destroys  either 
the  pollen  or  the  stigmatie  surface,  and  fertilization  fails  to  take  place. 

Most  of  the  patches  in  southern  California  have  apparently  devel- 
oped from  a  single  seed,  hence  are  usually  of  one  sex  only,  and  the 
development  of  seed  is  impossible. 

In  company  with  Earl  L.  Morris  and  G.  W.  Wardwell,  I  examined 
a  large  number  of  female  heads  in  various  localities  of  the  Santa  Ana 
delta  section  this  season  (1920)  but  was  unable  to  find  a  single  via  hit- 
seed. 

That  seeds  are  occasionally  formed  in  certain  years  is  not  improbable, 
although  its  spread  in  that  section  can  be  explained  by  its  introduction 
as  an  impurity  in  imported  beet  seed  and  by  the  washing  down  of 
pieces  of  the  rootstock  from  lands  upstream  during  the  heavy  floods 
which  occasionally  occur. 

In  spite  of  the  handicap  of  not  producing  seed,  the  Canada  thistle 
is  an  exceedingly  unwelcome  intruder.  Its  rootstocks  are  not  infre- 
quently twenty  feet  long,  producing  plants  at  frequent  intervals,  and 
being  exceptionally  persistent  in  the  face  of  control  measures.  In 
fact,  the  only  means  known  to  eradicate  it  is  to  prevent  it  from  forming 
green  leaves  over  a  period  of  two  years. 


BEAN  WEEVILS  IN  CALIFORNIA.' 

i:\    ANDREW  O.   LARSON^  Alhambra,   Caliform';i. 
LOSSES    FROM    BEAN    WEEVILS. 

According  to  statements  from  officials  of  the  California  Bean  Growers' 
Association,  and  others,  who  are  prominent  in  the  bean  industry  in 
California,  losses  caused  by  bean  weevils3  have  been  gradually  increasing 
year  by  year  until  1918  when  an  exceptionally  haevy  loss  was  sustained. 

Apparently  a  number  of  factors  combined  to  make  losses  greater  that 
year  than  ever  before.  Some  of  these  factors  are:  (1)  The  greater 
acreage  and  correspondingly  greater  yield;  (2)  early  planting  of  much 
of  the  crop;  (3)  spread  of  weevils,  through  seed  or  otherwise,  to  pre- 
viously uninfested  areas;  (4)  unusually  hot  weather  in  some  sections 
early  in  the  summer;  (5)  unseasonable  rains  early  in  September;  (6) 
shortage  of  labor. 

The  U.  S.  Bureau  of  Crop  Estimates  gives  the  acreage  of  1917  as 
558,000  and  the  California  Bean  Growers'  Journal,  Vol.  1,  No.  2,  page 
24,  estimates  the  yield  in  1917  as  3,616,000  centals  (100-pound  sacks)  ; 
while  in  1918  it  was  4,405,000  centals,  exclusive  of  limas,  which  are 
estimated  at  1,545,000  centals. 

According  to  H.  W.  Nimms  of  the  California  Bean  Growers'  Asso- 
ciation and  J.  E.  Clifford  of  the  Sacramento  Public  Bean  Cleaner,  and 
others,  the  early  beans  are  looked  upon  with  disfavor  and  are  put  onto 

'Published  with  the  approval  of  the  Secretary,  U.  S.   Dept.  of  Agriculture. 
2Scientiflc  Assistant,  Bureau  of  Entomology,  U.   S.  Dept.  of  Agriculture,  Alhambra, 

'Bruchus  obtectus  Say  and  B.  quadrimaculatus  Fab. 


THE   MONTHLY   BULLETIN.  345 

the  market  as  soon  as  possible  because  the  degree  of  infestation  is  likely 
to  be  high.  "They  are  good  beans  to  be  rid  of."  A  quotation  from 
the  Pacific  Rural  Press  of  April  12,  1919,  while  of  questionable 
value  in  itself,  gives  the  opinion  quite  generally  held  by  many  of  the 
leading  bean  growers : 

AVOID   BEAN    WEEVILS. 

"To  avoid  weevils  in  Lady  Washington  beans,  David  Klotc  of  Sacra- 
mento County  believes  July  planting  works.  In  1917  he  planted  a  few 
in  his  garden  late  in  May  and  got  about  100  pounds,  all  'buggy.'  In 
1918  he  planted  about  July  7  and  got  no  bugs,  though  a  neighbor  with 
three  acres  planted  about  June  1,  1918,  harvested  21  sacks,  '  alive  with 
bugs.'  Mr.  Kioto's  beans  matured  in  fine  shape  from  July  planting, 
as  this  variety  requires  only  about  90  days." 

"While  some  bean-growing  sections  such  as  Salinas  and  Lornpoc  are 
free  from  weevil  injury,  other  sections,  notably  points  in  the  San 
Fernando  Valley,  reported  weevil  injury  in  1918  for  the  first  time. 

Various  parts  of  California  reported  unusually  hot  weather  in  July 
and  August,  causing  bean  blossoms  to  fall  and  early  beans  to  ripen 
prematurely. 

The  north  and  central  parts  of  the  state  received  an  unprecedented 
amount  of  rainfall  beginning  about  September  11  and  continuing  until 
early  in  October.  It  did  a  great  amount  of  damage  to  prunes,  raisins 
and  beans.  The  rainfall,  together  with  the  shortage  of  labor,  made 
it  necessary  for  the  beans  to  remain  in  the  fields  longer  than  usual 
before  thrashing.  The  labor  shortage  was  also  felt  in  the  warehouses, 
where  many  of  the  beans  were  stored  before  they  were  properly  dried. 
Many  of  the  warehouse  men  claim  that  beans  which  have  been  rained 
on  "always  get  buggy." 

Whether  the  foregoing  or  other  reasons  caused  the  greater  activity  of 
the  weevils,  the  fact  is  that  they  caused  an  enormous  loss  estimated  at 
from  2  to  33  per  cent  of  the  crop,  according  to  the  variety  of  beans. 
While  exact  figures  are  not  available,  estimates  from  various  well- 
informed  men  from  the  bean  centers — Sacramento,  San  Francisco, 
Stockton.  Modesto,  Los  Angeles  and  San  Diego — all  agree  that  the 
above  estimate  is  conservative..  David  F.  Lane,  general  manager  of 
the  Turlock  Merchants'  and  Growers'  Association,  Inc.,  said:  "My 
idea  is  that  one-third  of  the  crop  of  1918  was  infested  with  weevil.  I 
do  not  think  this  is  exaggerating.  I  base  this  percentage  on  the  amount 
of  offerings  or  samples  that  we  take  during  the  day.  Out  of  eight  lots 
we  have  had  to  turn  down  four,  and  out  of  twelve  lots,  ordered  to  be 
inspected  by  a  certain  bank,  we  had  to  turn  down  four.  In  taking  a 
general  average  of  all  beans  offered  us  during  the  week  I  do  not  think 
that  Ave  have  been  able  to  accept  more  than  66  2/3  per  cent."  While 
this  undoubtedly  is  true  in  a  very  large  bean-growing  section  adjacent 
to  Turlock.  Modesto  and  Merced,  it  seems  too  high  for  the  entire  state. 
J.  Waterman  of  the  Waterman  Selling  Agency  in  Los  Angeles  and 
Oxnard,  said:  "Ten  per  cent  injury  from  bean  weevils  to  all  varieties 
of  beans  in  this  state  is  very  conservative.  While  it  is  a  little  too  high 
for  limas,  it  is  far  too  low  for  some  other  varieties,  notably  pinks,  black- 
eyes  and  whites."  Accepting  Mr.  Waterman's  estimate  of  damage  and 


346  THE    MONTHLY   BULLETIN. 

5,150,000  as  the  number  of  centals  of  beans  produced  and  8  cents  per 
pound  as  the  value  of  the  beans  (which  in  the  fall  of  1918  was  low 
until  the  importation  of  Oriental  beans  broke  the  market)  we  have  a 
loss  of  515,000  sacks  of  beans,  worth  $8  per  sack,  or  $4,120,000.  If 
this  estimate  is  even  cut  in  half,  the  loss  is  still  enormous. 

IDENTITY  OF  WEEVILS  CAUSING  DAMAGE  TO  BEANS. 

As  far  as  the  writer  has  been  able  to  learn,  this  injury  is  all  caused 
by  two  species,  the  four-spotted  weevil  (Bruchus  quadrimaculatus  Fab.) 
and  the  common  bean  weevil  (Bruchus  obtectus  Say.).  Before  this 
investigation  began,  it  was  supposed  that  the  common  bean  weevil  was 
causing  all  the  damage,  as  B.  quadrimaculatus  had  not  been  reported  in 
the  state.  However,  the  writer  finds  that  W.  B.  Parker  collected  speci- 
mens of  this  species  in  El  Centre  in  1913.  It  is  now  quite  widely 
distributed,  specimens  having  been  taken  by  the  writer  from  Sacra- 
mento, Lodi,  Stockton,  Ripon,  Los  Angeles,  "Wilmington,  Huntingtoii 
Beach,  Santa  Ana,  Puente  and  Corona. 

NOTES  ON  BRUCHUS  QUADRIMACULATUS. 

Bruchus  quadrimaculatus  confines  its  operations  to  black-eyed  cow- 
peas,  as  far  as  the  writer  has  observed,  but  others,  notably  Dr.  E.  A. 
Back  (Farmers'  Bulletin  983)  reports  it  attacking  other  varieties  of 
peas  and  beans.  This  led  the  writer  to  try  to  rear  it  on  Mexican  reds, 
pinks  and  Lady  Washingtons.  After  daily  observations  as  to  the  variety 
of  bean  on  which  it  prefers  to  oviposit,  the  writer  concluded  that  its 
preference  was  in  the  following  order:  first,  Mexican  reds;  second, 
pinks;  third,  blackeyes;  and  fourth,  Lady  Washingtons.  Because  of 
this  decided  preference  for  the  Mexican  reds  and  also  because  the  eggs 
can  be  seen  most  easily  on  that  variety,  it  was  used  for  making  daily 
records  of  the  number  of  eggs  deposited  by  each  of  a  series  of  females 
during  their  lives.  As  a  result,  eggs  were  laid  by  each  female  on  all 
varieties  but  principally  on  Mexican  reds.  All  the  eggs  were  put 
together  in  one  container  for  each  day.  Towards  the  latter  part  of 
the  series  only  Mexican  reds  were  used.  Between  July  7  and  25,  5718 
eggs  were  deposited;  of  these  2661  were  on  Mexican  reds  having  no 
other  variety  among  them.  Of  the  other  3057  eggs,  the  majority  were 
on  Mexican  reds  and  358  weevils  emerged  from  the  black-eyed  cowpeas. 
Approximately  two-thirds  of  the  eggs  deposited  on  black-eyed  cowpeas 
produced  adult  weevils,  while  not  a  weevil  emerged  from  the  other 
varieties  of  beans.  The  young  larvae  in  some  instances  had  bored  into 
the  cotyledons  of  beans  other  than  blackeyes  far  enough  to  show  tiny 
cavities  after  the  testa  had  been  removed,  but  usually  the  larva?  died 
while  trying  to  bore  their  way  through  the  testa. 

The  length  of  time  required  for  the  life  cycle  varies  not  only  with 
temperature  and  moisture  but  also  with  the  offspring  of  single  pairs 
where  the  eggs  were  deposited  within  a  few  seconds  or  minutes  of  each 
other  and  were  kept  in  the  same  small  container  until  emergence.  From 
90  eggs  deposited  on  77  black-eyed  cowpeas  June  7,  52  weevils  emerged, 
the  first  one  appearing  July  10  and  the  last  one  on  July  29 ;  while  from 
57  eggs  deposited  the  following  day  (June  8)  on  54  cowpeas  28  weevils 


THE    MONTHLY    BULLETIN.  347 

emerged,  the  first  one  on  July  8  and  the  last  on  July  25.  Of  a  lot 
of  196  eggs  deposited  August  15  a  variation  of  16  days  was  noted  from 
the  time  the  first  weevil  emerged  until  the  last  one  appeared.  Thus 
the  weevils  required  from  33  to  49  days  to  complete  their  life  cycle. 

During  the  period  June  8  to  December  18,  four  generations  have 
developed,  as  follows : 

(1)  June  8  to  July  8 — 30  days 

(2)  July  8  to  August  10—33  days. 

(3)  August  10  to  September  17 — 38  days. 

(4.)   September  17  to  December  18 — 92  days  (first  emergence  only). 

There  appears  to  be  little  if  any  difference  in  the  time  required  for 
the  development  of  males  and  females  but  when  confined  on  dry  beans 
or  cowpeas  the  life  of  the  adult  females  is  from  2  to  5  days  longer  than 
that  of  the  males.  During  the  summer,  the  females  lived  from  9  to  20 
days,  while  the  males  lived  from  7  to  19  days,  with  the  majority  living 
only  14  days. 

Mating  usually  takes  place  a  few  hours  after  emergence,  and  egg 
laying  begins  the  next  day,  but  sometimes  eggs  were  deposited  before 
the  weevils  were  24  hours  old  while  in  other  cases  several  days  elapsed 
before  oviposition  began.  The  number  of  eggs  laid  varies  daily  with 
the  same  individual  and  with  different  individuals,  the  greatest  number 
usually  being  deposited  when  the  weevil  is  about  3  days  old.  Thirty- 
nine  eggs  in  one  day  and  117  for  one  individual  are  the  highest  numbers 
recorded  by  the  writer.  In  summer,  85  is  about  the  average  for  one 
female.  The  following  is  a  typical  example:  (the  female  emerged 
September  20  and  died  October  6). 

Sept.  21 :22 :23 :24  :25  :26 :27 :28 :20 :30 :     Oct.  1 :2 :3 :4  :5 :6 

Eggs  15:17:  4:13:  6:15:  7:  0:  4:  0:     Eggs  2:0:0:1 :0:0    Total  84. 

So  far  as  the  writer  has  observed  in  the  field,  eggs  were  deposited  only 
on  the  pods  of  black-eyed  cowpeas,  usually  only  a  few  eggs  being  found 
on  a  pod ;  but  as  many  as  63  have  been  found  by  the  writer  on  one  pod. 
Apparently  the  weevil  prefers  to  oviposit  on  pods  where  the  cowpeas  are 
just  beginning  to  harden,  the  writer  having  never  observed  new-laid 
eggs  on  ripe  pods  where  green  ones  could  be  found.  The  eggs  are  laid 
singly  and  are  firmly  cemented  to  the  pod  in  the  field  or  the  bean  in 
storage.  As  the  young  larva  bores  its  way  through  the  under  surface 
of  the  egg  it  fills  the  eggshell  with  borings,  giving  the  shell  a  straw- 
white  appearance. 

NOTES  ON   BRUCHUS  OBTECTUS. 

The  habits  of  Bruchus  obtectus  are  quite  different  from  those  of 
B.  quadrimaculatus,  although  the  larval  stages  are  very  similar.  In  the 
field,  B.  obtectus  gnaws  a  hole  in  the  green  pod,  showing  a  dislike  for 
only  limas  and  teparies  among  the  many  varieties  observed  by  the 
writer.  However,  it  successfully  attacks  both  of  the  above  varieties. 
The  holes  are  gnawed  into  the  sides  of  the  pods  or  into  the  sutures,  pref- 
erably the  dorsal  suture.  After  a  hole  has  been  made  eggs  are  deposited 
therein.  Following  the  deposition  of  each  egg  the  weevil  turns  around 
and  uses  its  mouth-parts  to  force  the  egg  further  into  the  pod.  The 


348  THE   MONTHLY   BULLETIN. 

writer  has  observed  one  female  thus  deposit  14  eggs  in  5  minutes.  He 
has  counted  as  many  as  67  eggs  which  had  been  thus  inserted  into  one 
hole  adjacent  to  the  dorsal  suture.  While  this  weevil  inserts  its  eggs 
in  young,  tender  pods  it  prefers  to  find  pods  that  are  ripe,  as  these 
usually  crack  open  at  least  for  a  very  short  distance  along  the  dorsal 
suture.  These  tiny  openings  in  the  suture  are  found  and  the  eggs  are 
deposited  in  them  in  great  numbers.  The  early  beans  are  far  enough 
advanced  to  receive  eggs  before  the  later  pods  are  sufficiently  developed. 
When  the  early  pods  ripen  and  begin  to  crack  open  the  weevil  appar- 
ently confines  its  attack  to  them,  leaving  the  later  beans  free. 

In  stored  beans,  B.  obtectus  eggs  are  deposited  loose  among  the  beans 
so  that  a  little  agitation  causes  them  to  fall  to  the  bottom  of  the  con- 
tainer. A  casual  observer,  therefore,  does  not  see  the  eggs  at  all. 

It  appears  that  B.  obtectus  shows  more  uniformity  of  oviposition  and 
emergence  than  does  B.  quadriniaculatus.  Equal  numbers  of  eggs  of 
each  species  when  deposited  the  same  day  and  kept  under  like  condi- 
tions show  that  B.  quadrimaculatus  will  begin  to  emerge  from  two  to 
five  days  before  any  of  the  others  appear  but  it  also  continues  to  emerge 
several  days  after  B.  obtectus  is  through  emerging.  B.  obtectus  seldom 
oviposits  until  it  is  two  or  three  days  old;  then  it  deposits  a  fairly 
uniform  number  of  eggs  daily ;  the  daily  and  total  number  of  eggs  being 
as  a  rule  smaller  than  is  the  case  with  B.  quadrimaculatus.  The  period 
during  which  the  former  oviposits  is  the  greater. 

Typical  Examples  of  Egg- Laying  of  B,  obtectus.      Both  Emerged  June  30. 

July  1:  2:  3:  4:  5:  6:  7:  8:  9:10:11:12:13:14:15:16:17  :Total  :Died 
Eggs  0:15:15:  5:  5:  7:  5:  7:  4:  7:  2:  5:  0:  0:  0:  0:  0   :  77    :  7/22 
Eggs  0:10:12:  0:  0:11:  2:2:1:2:5:5:0:2:10:3:7    :72    :  7/24 

The  highest  number  the  writer  has  observed  from  one  female  in  one 
day  is  26  and  85  is  the  highest  total  recorded  by  him  for  the  life  of 
an  individual.  Probably  greater  numbers  are  deposited  in  the  field, 
as  the  writer  has  found  67  eggs  inside  a  pod  adjacent  to  one  puncture. 
He  has  recorded  the  emergence  of  35  weevils  from  three  pink  beans. 
the  contents  of  one  pod  having  only  one  puncture  when  collected.  He 
also  recorded  the  emergence  of  37  weevils  from  four  Lady  Washington 
beans,  the  contents  of  one  pod.  From  the  very  few  days  required  for 
the  emerging  period,  it  would  appear  that  the  eggs  in  each  pod  had 
been  deposited  the  same  day  if  not  by  the  same  female. 

MECHANICAL   DEVICES   IN   CONTROL  OF   BEAN   WEEVILS. 

Bean  dealers  frequently  suggest  that  a  mechanical  agitator  could  be 
made  which  would  be  capable  of  eliminating  the  weevil  in  stored  beans. 
This  led  the  writer  to  try  shaking  vigorously  each  day  a  vial  containing 
pink  beans  with  a  few  B.  obtectus  and  their  eggs.  On  June  26,  ten 
weevils  were  put  on  58  beans  in  a  glass  container;  they  were  shaken 
vigorously  each  day.  No  weevils  were  removed  until  the  last  one  was 
dead  and  the  eggs  were  left  in  the  vial.  August  13  emergence  began 
and  116  emerged  between  that  date  and  August  21.  On  examining 
the  beans  after  August  21  they  were  found  to  contain  36  dead  larva?, 
i  pupa3  and  14  adults,  all  dead.  Of  these,  one  adult  and  31  larvae  had 
evidently  starved  in  one  bean.  There  were  28  beans  containing  no 


THE   MONTHLY   BULLETIN. 


349 


weevils.  A  check  of  48  beans  and  ten  weevils,  receiving  the  same  treat- 
ment except  for  shaking,  showed  emergence  of  266  between  August  7 
and  19.  Later  examination  showed  4  larvae,  5  pupae,  and  14  adults  dead 
within  the  beans.  Only  12  beans  were  free. 

A  revolving  cylinder  with  finely  perforated  walls  would  probably 
be  effective  on  a  small  scale.  It  could  be  turned  a  few  minutes  every 
fourth  day  in  warm  weather  and  would  throw  out  the  eggs  which  had 
been  deposited  since  the  last  agitation.  This,  however,  would  be  of  no 
use  in  controlling  B.  quadrimaculatus  because  the  eggs  are  cemented 
too  firmly  to  the  bean.  The  expense  of  operating  would  prohibit  its 
use  commercially  as  a  control  for  B.  obtectus. 

FUMIGATION     IN    CONTROL    OF    BEAN    WEEVILS. 

The  results  of  numerous  fumigation  tests  with  carbon  disulphide 
show  it  to  be  an  effective  means  of  control  in  the  warehouse.  The  fol- 
lowing data  shows  the  efficiency  of  fumigation  when  done  properly. 
The  sample,  200  beans,  was  taken  from  a  lot  of  badly-infested  cranberry 
beans  which  had  been  fumigated  48  hours  with  six  pounds  of  carbon 
disulphide  to  900  cubic  feet. 

Results   of    Fumigating    Infested    Beans   With   Carbon    Disulphide. 


Number  of  beans 

Number* 
weevils 
in  each 

Per  cent 
of  sample 

Adults             Pupae 

Larvse 

P£STt 

41 

o 

205 

1 

19.5 

40 

2 

20.0 

24 

3 

120 

91 

4 

100 

14    

5 

7.0 

9 

0 

4  5 

7 

7 

3  5 

1 

A. 

5 

2 

t) 

10 

"T"  

2 

10 

1.0 

1 

12 

5 

" 

200    .             

100.0 

1                   108 

393 

100 

Later  trials  show  that  the  eggs  also  are  killed  by  this  treatment,  the 
writer  finds. 

NATURAL    ENEMIES. 

Undetermined  chalcids  have  been  found  working  on  B.  quadrimacu- 
latus, and  a  predaceous  mite,  determined  by  Dr.  Ewing  as  probably 
Pediculoides  ventricosus  Newport,  has  been  found  by  the  writer  attack- 
ing both  species.  While  the  mite  is  a  very  effective  check  in  the 
laboratory,  it  causes  so  much  human  discomfort  that  its  use  is  not  to 
be  recommended. 


350  THE   MONTHLY   BULLETIN. 


QUARANTINE;  «fah)i  SERVICE 


REPORT  FOR  THE  MONTH  OF  JUNE,  1920. 

By  FREDERICK  MASKEW. 

SAN    FRANCISCO    STATION. 

Steamship   and    baggage   inspection: 

Ships    inspected    88 

Passengers  arriving  from  fruit-fly  ports 5,901 

Horticultural   imports:  Parcels 

Passed  as  free  from  pests 76,673 

Fumigated    1,593 

Refused    admittance 38 

Contraband    destroyed    130 


Total  parcels  horticultural  imports  for  the  month 78.434 

PESTS    INTERCEPTED. 
From    Central   America: 

Pseudococcus   sp.   and  Aspidiotus  cycmophylli   on   bananas. 
From  China: 

Formicid   (undetermined)   in  water  chestnuts. 
Lepidopterous   larva   in   dry  herbs. 
Larva  of  borers   (undetermined)    in  twigs. 

From   Hawaii: 

Diaspis  bromeliae  and  Pseudococcus  bromeliae  on  pineapples. 

Larva  of  Trypetid   (undetermined)   in  tomatoes. 

Coccus  elongatus  and  Aphis  sp.  on  betel  leaves. 

Hemichionaspis  minor  on  red  peppers. 

Saissetia  nigra  and  Pseudaonidia  duplex  on  hibiscus  cuttings. 

From    Japan: 

Fungus   (undetermined)   on  Japanese  pears. 

Lepidopterous  larva   (undetermined)    in  dried  chestnuts  and  dried  fruit. 
From   Mexico: 

Calandra  sp.  and  Silyanus  surinamensis  In  squash  seed. 
Lepidosaphes  gloverii  and   Chrysomphalus  aurantii  on   limes. 

From    New  Zealand: 

Larva  of  Diptera  (undetermined)  in  decayed  potatoes. 
From  Oregon: 

Actinomyces  scabies,  Rhieoctonia  and   F'usarium  on  potatoes. 

Epochra  canadensis  In  gooseberries. 

From   Pennsylvania: 

Pseudococcus  sp.  on  Gardenia. 
From  San  Salvador: 

Lepidosaphes  gloverii  and  Lepidosaphes  beckii  on  limes. 
From   Washington: 

Actinomyces   scabies,   Rhizoctonia   and   Fusarium   on   potatoes. 

LOS  ANGELES   STATION. - 
Steamship  and    baggage   inspection: 

Ships  inspected 56 

Fish    boats    inspected •      7 

Passengers  arriving  from  fruit-fly  ports 11 


THE    MONTHLY    BULLETIN.  351 

Horticultural    imports:  Parcels 

Passed  as  free  from  pests __  65,891 

Fumigated    12 

Refused  admittance 24 

Contraband  destroyed 21 


Total  parcels  horticultural  imports  for  the  month 65,948 

PESTS    INTERCEPTED. 
From   Alabama: 

Melanose   and   Lepidosaphes   beckii  on   grapefruit. 
From  Central  America: 

Pseudococcus  sp.,  Aspidiotus  ctidoniae  and  Aspidiotus  cyanophylli  on  bananas. 
From   Cuba: 

Diaspis  bromeJiae  on  pineapples. 
From   Illinois: 

Lecanium    corni    on    black    currant    bushes. 
From    Mexico: 

Unidentified  weevils  in  tamarinds. 

Anastrepha  ludens  in  mangoes. 

Chloridea  obsoleta  in  tomatoes. 

From   New  York: 

Green  aphis  and  Tetranychus  sp.  on  chrysanthemum  plants. 

Melanose,  unidentified  fungus  and  Lepidosaphes  beckii  on  Cuban  grapefruit. 

Melanose  and  Lepidosaphes   beckii  on   Florida  grapefruit. 

From   Ohio: 

Green  aphis  on  chrysanthemum  plants. 
From   Oregon: 

Rhizoctonia  on  potatoes. 
From    Philippine    Islands: 

Larva  on  weevil  in  sweet  potatoes. 
From  Texas: 

Tetranychus    mytttaspidis,    Aleyrodes    sp.    and    Ceroplastes    floridensis    on    Cape 
jessamine  buds. 

SAN    DIEGO    STATION. 

Steamship    and    baggage    inspection: 

Ships    inspected    22 

Fish  boats  inspected  

Passengers  arriving  from  fruit-fly  ports 40 

Horticultural   imports:  Parcel* 

Passed  as   free   from   pests 6,436 

Fumigated    

Refused  admittance 

Contraband    destroyed    

Total  parcels  horticultural  Imports  for  the  month —  --  6.451 

PESTS    INTERCEPTED. 
From    Central    America: 

Aspidiotus  cyanophylli,  Aspidiottts  sp.  and  Pseudococcus  sp.  on  bananas. 
From    Mexico: 

Diatraea  saccharalis  in  sugar-cane. 
From    North    Dakota: 

Rhizoctonia  on  potatoes. 
From    Utah: 

Rhizoctonia  on  potatoes. 


EUREKA    STATION. 

Steamship    and    baggage    inspection: 

Ships   inspected  

Passengers  arriving  from  fruit-lly  i 

Horticultural   imports: 

Passed   as   free   from   i 

i  i 
5092     8-20     TM 


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